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2016cosp...41E2150Z | The Algerian forests are characterized by a particularly flammable material and fuel. The wind the relief and the slope facilitates the propagation of fire. The use of remote sensing data multidates combined with other types of data of various kinds on the environment and forest burned opens up interesting perspectives for the management of postfire regeneration. In this study the use of multitemporal remote sensing image Alsat1 and Landsat combined with other types of data concerning both background and burned down forest appears to be promising in evaluating and spatial and temporal effects of post fire regeneration. A spatial analysis taking into consideration the characteristics of the burned down site in the North West of Algeria allowed to better account new factors to explain the regeneration and its temporal and spatial variation. We intended to show the potential use of remote sensing data from satellite ALSAT1 of spatial resolution of 32 m. . This approach allows showing the contribution of the data of Algerian satellite ALSAT in the detection and the well attended some forest fires in Algeria. | 2016-07-01T00:00:00Z | ['2016cosp...41E2150Z'] | null | Forest Fires and Post Fire Regeneration in Algeria Analysis with Satellite Data | 2,016 | 0 | 0.14 | null | 0 | null |
2017Ap&SS.362...27Y | A new method of obtaining bounded trajectories near collinearlike equilibrium points of elongated asteroids using a simple linear control is proposed. The characteristic equation of the linearized equation of motion near the collinearlike equilibrium points is reduced based on the property of the second derivatives of the effective potential. According to the reduced characteristic equation the motion is decoupled into an inplane motion and a outofplane motion. The solutions to the decoupled equation of motion are derived and the corresponding Lissajous trajectories are chosen as desired trajectories. A simple linear control which tracks the Lissajous trajectories is formulated with the stability conditions of gains. The effectiveness of the proposed method is validated by simulations using high fidelity models of 216 Kleopatra and 951 Gaspra. | 2017-02-01T00:00:00Z | ['2017Ap&SS.362...27Y', '10.1007/s10509-017-3007-1'] | ['Asteroid', 'Equilibrium point', 'Effective potential', 'Lissajous trajectory', 'Linear control'] | Bounded trajectories near collinearlike equilibrium points of elongated asteroids using linear control | 2,017 | 0 | 0.22 | ['PUB_HTML'] | 10 | null |
2017Ap&SS.362..120P | The goal of this research is to study the energy variations in trajectories of a spacecraft that performs a powered aerogravityassist maneuver considering the effects of the lift and drag forces around the Earth. It means that the spacecraft makes a passage by the Earth that is close enough to get effects from the atmosphere. Besides those effects an impulse is applied to the spacecraft when it is passing by the periapsis of the trajectory which also helps to modify its trajectory. It is varied the ballistic coefficient lift to drag ratio magnitude and direction of the impulse and the angle of approach of the maneuver. The mathematical model assumes that a spacecraft comes from an orbit around the Sun traveling under the restricted threebody problem dynamics makes a close approach passing inside the atmosphere of the Earth and then goes back to another orbit around the Sun which is different from the initial orbit. The initial position and velocity of the spacecraft are given according to the usual pure gravityassisted parameters using the angle of approach and the perigee altitude and velocity. The energy is measured before and after the passage. The equations of motion are numerically integrated using a RungeKuttaFehlberg 78 method. For the numerical examples the perigee altitude is fixed in 120 km and the velocity at this point is fixed in 0.5 canonical units which is near 14.89 kms. | 2017-07-01T00:00:00Z | ['2017Ap&SS.362..120P', '10.1007/s10509-017-3097-9'] | ['Astrodynamics', 'Aero-gravity-assist maneuvers', 'Swing-by', 'Restricted three-body problem', 'Impulsive maneuvers', 'Flyby'] | Powered aerogravityassist maneuvers considering lift and drag around the Earth | 2,017 | 0 | 0.21 | ['PUB_HTML'] | 9 | null |
2017AntAs..11....2H | Scottishborn astronomer Williamina Paton Stevens Fleming 18571911 worked closely for three decades with the Director of Harvard College Observatory HCO Edward Charles Pickering 18461919. Fleming performed a pivotal role in the Henry Draper Memorial project on stellar spectra and led the Harvard team of female computers serving as the observatorys Curator of Astronomical Photographs between 1899 and 1911. This paper reviews her contribution to the growth of HCO and her leadership of Pickerings women assistants using archived correspondence journals annual reports and contemporary accounts. Her mentoring role is examined particularly in regard to Annie Jump Cannon 18631941 who succeeded her at Harvard and further developed the Harvard spectral classification system. A new assessment of the contribution made by Fleming to the success of Pickering and the HCO is discussed. | 2017-06-01T00:00:00Z | ['2017AntAs..11....2H'] | null | Williamina Fleming and the Harvard College Observatory | 2,017 | 0 | 0.4 | ['ADS_PDF', 'ADS_SCAN'] | 0 | null |
2017ATel10961....1C | ePESSTO the extended Public ESO Spectroscopic Survey for Transient Objects see Smartt et al. 2015 A amp A 579 40 httpwww.pessto.org reports the following supernova classifications. | 2017-11-01T00:00:00Z | ['2017ATel10961....1C'] | ['Supernovae'] | ePESSTO spectroscopic classification of optical transients | 2,017 | 0 | 0.06 | ['PUB_HTML'] | 0 | null |
2017ATel11062....1S | ePESSTO the extended Public ESO Spectroscopic Survey for Transient Objects see Smartt et al. 2015 A amp A 579 40 httpwww.pessto.org reports the following supernova classifications. | 2017-12-01T00:00:00Z | ['2017ATel11062....1S'] | ['Supernovae'] | ePESSTO spectroscopic classification of optical transients | 2,017 | 0 | 0.06 | ['PUB_HTML'] | 1 | null |
2017CQGra..34q7002M | A concise form of the asymptotically flat metrics describing the simplest magnetic generalizations of the Kerr and KerrNewman spacetimes is presented. The explicit formulae for the corresponding electromagnetic potentials are also given together with simple expressions of all metric functions in the equatorial plane. It is shown that the magnetic field changes the structure of the gravitational multipole moments of the vacuum Kerr solution. | 2017-09-01T00:00:00Z | ['10.1088/1361-6382/aa80bb', '2017CQGra..34q7002M'] | null | A note on magnetic generalizations of the Kerr and KerrNewman solutions | 2,017 | 0 | 0.17 | ['PUB_HTML'] | 4 | null |
2018cosp...42E2293M | The Floating Potential Measurement Unit FPMU instrument suite on the International Space Station ISS provides redundant measurements of the electron density electron temperature and spacecraft potential along the ISS orbit. Deployed in August 2006 the FPMU includes a Wide Langmuir Probe Narrow Langmuir Probe Floating Potential Probe and a Plasma Impedance Probe. The instruments are used for ISS engineering applications ISS science payload support and collaboration with the ionospheric science community. FPMU provides insitu observations of plasma density and temperature at or above the peak plasma density in the F2region ionosphere due to the typical 350 km to 400 km flight altitude of the ISS. This presentation will first compare the insitu FPMU measurements of electron density and temperature with the IRI2016 model and COSMIC radio occultation measurements of electron density. We then describe FPMU data that is now available to the space science community through NASAs Space Physics Data Facility providing a new source of topside ionosphere plasma density and temperature values for use in working with the IRI model other ionospheric physics models and other satellite and ground based observations. | 2018-07-01T00:00:00Z | ['2018cosp...42E2293M'] | null | Comparing ISS FPMU Topside Electron Densities with IRI2016 Model and COSMIC Radio Occultation Measurements | 2,018 | 0 | 0.22 | null | 0 | null |
2017CQGra..34e5009G | In this paper we investigate whether the holographic principle proposed in string theory has a classical counterpart in general relativity theory. We show that there is a partial correspondence at least in the case of vacuum Petrov type D spacetimes that admit a nontrivial Killing tensor which encompass all the astrophysical black hole spacetimes there exists a onetoone correspondence between gravity in bulk and a 2dimensional classical conformal scalar field on a null boundary. | 2017-03-01T00:00:00Z | ['10.1088/1361-6382/aa5dc0', '2017CQGra..34e5009G'] | null | 4dimensional spacetimes from 2dimensional conformal null data | 2,017 | 0 | 0.12 | ['PUB_HTML'] | 2 | null |
2024JPlPh..90b9702O | A new magnetic mirror machine named KAIMIR KAIST mirror has been designed and constructed at the Korea Advanced Institute of Science and Technology KAIST to study mirror plasma physics and simulate the boundary regions of magnetic fusion plasmas such as in a tokamak. The purpose of this paper is to introduce the characteristics and initial experimental results of KAIMIR. The cylindrical vacuum chamber has a length of 2.48 m and a diameter of 0.5 m and consists of three subchambers namely the source centre and expander chambers. A magnetic mirror configuration is achieved by electromagnetic coils with a maximum magnetic field strength of 0.4 T at the mirror nozzles and 0.1 T at the centre. The source plasma is generated by a plasma washer gun installed in the source chamber with a pulse forming network system. The typical discharge time is 12 ms with a 6 ms 17 ms steady period. Initial results show that the onaxis electron density at the centre is 10SUP1920SUP mSUP3SUP and the electron temperature is 47 eV. Two parameters were varied in this initial phase the source power and the mirror ratio which is the ratio of highest to lowest magnetic field strength in the mirrorconfined region. We observed that the increase of the electron density was mitigated for a source power above 0.2 MW. It was also found that the electron density increases almost linearly with the mirror ratio. Accordingly the stored electron energy was also linearly proportional to the mirror ratio similar to the scaling of the gas dynamic trap. | 2024-04-01T00:00:00Z | ['2024JPlPh..90b9702O', '10.1017/S0022377824000242'] | ['magnetic mirror', 'plasma devices', 'gas dynamic trap'] | Development of a new magnetic mirror device at the Korea Advanced Institute of Science and Technology | 2,024 | 0 | 0.32 | ['PUB_HTML', 'PUB_PDF'] | 1 | null |
2016xmm..prop..165W | Following a series of remarkable recent discoveries we now know thatsome of the most luminous members of the ultraluminous Xray source ULXpopulation are actually powered by apparently superEddington neutronstar accretors. Three such systems are now known M82 X2 NGC7793 P13and NGC5907 ULX1. Here we propose a series of XMMNewton observationsof P13 two of which will be coordinated with NuSTAR in order to trackthe evolution of the pulse period test the proposed orbital nature ofthe 64d optical period and investigate changes in both the average andthe pulsephase resolved emission as a function of flux for comparisonwith the broader ULX population. Out of the three ULX pulsars currentlyknown the low absorption and lack of source confusion make P13 theideal candidate for this study. | 2016-10-01T00:00:00Z | ['2016xmm..prop..165W'] | null | Tracking the Neutron Star ULX NGC 7793 P13 with XMMNewton and NuSTAR | 2,016 | 0 | 0.19 | null | 0 | null |
2016xrp..prop...71V | NonLTE emission can be much greater than the intrinsic planetary emission due to stellar flux amplifications via fluorescence cascades and it may provide a new means to characterize the composition of exoplanets. Are we properly interpreting exoplanet spectra using current emission models Can molecular signatures be detected in these intriguing newly discovered hazy exoplanets Nonequilibrated nonLTE emission may hold the answer. We propose to model nonequilibrated emission in exoplanets for several key species H2O CH4 CO2 CO NH3 and HCN incorporating comprehensive highenergy databases containing billions of spectral lines realistic climate models and advanced radiative transfer models. Specifically we propose the following tasks Compile a set of density and temperature profiles for exoplanets at different distances from the hoststar radius and density by making use of our 1D coupled climatephotochemistry model. Compile a realistic set of highresolution stellar spectra covering a broad range of host stars by combining theoretical and astronomical data. Develop highenergy and selfconsistent linelists for CH4 CO and CO2 applicable to highresolution spectra building on our work for H2O NH3 and HCN. Compute nonLTE branching rates cascades and probabilities for the 80 exoplanetary cases making use of our General Fluorescence Model GFM. Synthesize nonLTE spectra by integrating the computed cascade probabilities and LTE fluxes for the equilibrated regions of the atmosphere leading to 80 highresolution templates for 6 molecules. Compare the templates to the known exoplanet population to predict which planets would be the best candidates for detection of nonLTE emission using current and nearterm observational resources HST KeckVLT JWST WFIRST and ELT. This proposal is highly consistent with the goals of the ROSES Exoplanets Research Program in that the proposed nonLTE modeling directly supports the goal of understanding exoplanetary systems by aiding in the detection of molecular signatures of exoplanets helping to explain current and future observations of exoplanetary systems and by constraining the chemical and physical processes active in exoplanets. | 2016-01-01T00:00:00Z | ['2016xrp..prop...71V'] | null | Modeling of NonEquilibrated Emission from Exoplanets for a Broad Range of Temperatures Host Stars and Molecules H2O CH4 CO2 CO NH3 HCN | 2,016 | 0 | 0.06 | null | 0 | null |
2016tac..confE..16B | Hydrocarbons formed in Titans cold atmosphere starting with ethane C2H6 ethylene C2H4 acetylene C2H2 propane C3H8... up to benzene C6H6 play some role in aerosol production cloud processes rain generation and Titans lakes formation. We have started to study in the laboratory the kinetics of the first steps of condensation of these hydrocarbons. Rate coefficients are very sensitive to the description of the potential interaction surfaces of the molecules involved. Combined theoretical and experimental studies at the molecular level of the homogenous nucleation of various small molecules should improve greatly our fundamental understanding. This knowledge will serve as a model for studying more complex nucleation processes actually taking places in planetary atmospheres. Here we present the first experimental kinetic study of the dimerization of two small hydrocarbons ethane C2H6 and propane C3H8. We have performed experiments to identify the temperature and partial densities ranges over which small hydrocarbon clusters form in saturated uniform supersonic flows. Using our unique reactor based on a Laval nozzle expansions the kinetics of the formation has also been investigated down to 23 K. The chemical species present in the reactor are probed by a time of flight mass spectrometer equipped with an electron gun for soft ionization of the neutral reagents and products. This work aims at putting some constraints on the role of small hydrocarbon condensation in the formation of haze particles in the dense atmosphere of Titan. | 2016-06-01T00:00:00Z | ['2016tac..confE..16B'] | null | Poster 4 Investigating the first steps of hydrocarbon condensation in the laboratory and in Titans atmosphere | 2,016 | 0 | 0.06 | null | 0 | null |
2016tac..confE...4S | Previous work e.g. Snowden et al. 2014 showed that energy deposition rates in Titans atmosphere due to the precipitation of magnetospheric electrons and ions are small compared to the energy flux due to solar EUV. However some of these results relied on energy flux rates at Titans exobase calculated from Voyager 1 data or data from a small number of Cassini flybys. Cassini has shown that the plasma environment around Titan is extremely variable and that the Voyager 1 conditions are not characteristic of an average plasma environment. Therefore we further investigate the issue using particle tracing simulations for ions and a two stream model for electrons in combination with a 3D model of Titans induced magnetosphere. We find that energy deposition and ionization rates in Titans atmosphere do not only depend on the upstream energy distribution of magnetospheric plasma near Titan e.g. plasma sheet or lobelike but also on the characteristics of Titans Alfven wing structure and the strength of the induced field. Surprisingly we find that the energy deposition and ionization rates in Titan upper atmosphere may be higher when Titan is in Saturns magnetospheric lobes due reduced shielding of magnetospheric ions. Our simulations confirm that the globally averaged energy deposition rates due to magnetospheric particles are smaller than solar radiation. | 2016-06-01T00:00:00Z | ['2016tac..confE...4S'] | null | Explaining the high electron density observed during T57 | 2,016 | 0 | 0 | null | 0 | null |
2016yCat..51520111A | Our survey was designed to obtain 40 sq.deg. of highcadence sky coverage near the right ascension R.A. of 2hr. Despite the severe weather and technical problems in 2011 and 2012 we succeeded in obtaining highquality observations for 32 sq.deg. thanks to a robust survey design. The survey was conducted using MegaCam on the CanadaFranceHawaii Telescope CFHT on Maunakea Hawaii which was chosen for its combination of a large field of view almost 11 and a 3.58m diameter aperture providing the best combination of depth and coverage. Additionally the queueoperation of CFHT was crucial for the success of this survey which required many observations throughout two semesters but often only a couple of hours of observations in a given night. P The onsky pointings of the survey were chosen to be near Neptunes L4 Lagrange point where many Neptunian trojans reside and many n2 n3 and n4 resonances are near pericenter. The survey obtained one lowlat block of 20 sq.deg. 54 centered near the ecliptic plane and another highlat block of 12 sq.deg. 43 located 15 north. P Our survey needed to reach mSUBrSUB24.5 to detect objects with HSUBrSUB9.7 at 30au. This depth is more than a magnitude past the reported transition near HSUBrSUB8.50.2. P The discovery observations for each field were a set of three 320s exposures plus 40s overhead separated by 1hr triplets 10 fields could thus obtain discovery images in a threehour block. P Our fields obtained discovery observations in 2011 and 2012 October. Our lowlat block was divided horizontally into two 10 sq.deg. subblocks obtaining triplets as described above. The southern half obtained discovery observations on 2011 October 24 and the northern half on 2011 October 26 with image qualities mostly in the range 0.50.6. The highlat block obtained discovery triplets in 2012 October with image qualities ranging from 0.5 to 0.8. The 2012 October highlat discovery block was divided vertically into two 6 sq.deg. subblocks. The discovery triplets consisted of the six fields of the subblock interspersed with single images nailing images of fields from the other subblock to extend the interval between subsequent images of the triplets up to near an hour. The western half obtained discovery observations on 2012 October 20 the eastern half was observed on 2012 October 21. P Objects were tracked for up to 28 months of total arc. P 1 data file. | 2016-11-01T00:00:00Z | ['10.26093/cds/vizier.51520111', '2016yCat..51520111A'] | ['Solar system', 'Minor planets', 'Surveys', 'Magnitudes'] | VizieR Online Data Catalog A 20112013 survey of transNeptunian objects Alexandersen 2016 | 2,016 | 0 | 0.12 | ['PUB_HTML'] | 0 | null |
2016tac..confE...6C | The Cassini Plasma Spectrometer CAPS has observed heavy positive ions with masses up to approximately 300 amu as well as negative ions with even higher masses. The abundance and density of these positive ions have been reported for selected encounters especially during those where comparisons with Ion and Neutral Mass Spectrometer INMS data are possible. The present work presents a survey of all available encounters showing the density of ions in various mass ranges and their spatial distribution. The influence of the broad mass distribution on ionospheric conductivity will also be discussed. | 2016-06-01T00:00:00Z | ['2016tac..confE...6C'] | null | A survey of heavy ions in Titans ionosphere | 2,016 | 0 | 0.06 | null | 0 | null |
2016yCat..22260007C | We select our FGK stellar sample from the allsky Transiting Exoplanet Survey Satellite TESS Dwarf Catalog TDC Stassun et al. 2014 arXiv1410.6379. We extract timeseries photometry from the target pixel files provided by the K2 project using circular stationary softedged apertures. See section 2 for further explanations. P We obtained highresolution optical spectra of 83 planet candidate hosts using the HIRES echelle spectrometer on the 10m Keck I telescope R55000. We obtained spectra of 27 candidate host stars using the Levy highresolution optical spectrograph mounted at the Automated Planet Finder APF R80000 or 100000. We obtained spectra of a small number of candidate stellar hosts using the FEROS fiberfed echelle spectrograph at the 2.2m MPG telescope R48000. See section 3.1 for further details. P We obtained highresolution imaging HRI for 164 of our candidate systems. Our primary instrument for this work was NIRC2 at the 10m Keck II telescope with which we observed 110 systems. As part of multisemester program GN2015BLP5 PI Crossfield at Gemini Observatory we observed 40 systems with the NIRI camera in the Kband. We also observed 33 stars with PHAROPALM3000 at the 5m Hale Telescope and 14 systems with LMIRCam at LBT all at the Kband. We observed 39 stars at visible wavelengths using the automated RoboAO laser adaptive optics system at the Palomar 1.5m telescope. Through our LongTerm Gemini program we also acquired highresolution speckle imaging of 32 systems in narrowband filters centered at 692 and 880nm using the DSSI camera at the Gemini North telescope. See section 3.3 for further explanations. P 7 data files. | 2016-10-01T00:00:00Z | ['10.26093/cds/vizier.22260007', '2016yCat..22260007C'] | ['Stars: double and multiple', 'Planets', 'Radial velocities', 'Stars: diameters', 'Stars: masses'] | VizieR Online Data Catalog Planet candidates discovered using K2s 1st yr Crossfield 2016 | 2,016 | 0 | 0.16 | ['PUB_HTML'] | 0 | null |
2016yCat..18270089T | The observations of Pisces A and B were taken as part of HST program GO13745 Cycle 22 PI Tollerud executed 2014 October 30November 8. Pisces A and B were observed for a single orbit each with ACSWFC using the F606W and F814W filters. P 2 data files. | 2016-11-01T00:00:00Z | ['2016yCat..18270089T', '10.26093/cds/vizier.18270089'] | ['Galaxies: nearby', 'Photometry: HST', 'Radial velocities'] | VizieR Online Data Catalog HST imaging of Pisces A and B Tollerud 2016 | 2,016 | 0 | 0 | ['PUB_HTML'] | 0 | null |
2024JPlPh..90b9704A | Collisionless charged particle motion and its transport in the twowire model TWM with no axial magnetic fields is investigated numerically. The TWM configuration contains a magnetic Xpoint and single particle motions in such a field have two conserved quantities the total kinetic energy and the base field line value which is a quantity derived from the axial canonical momentum. As gyrating particles travel along the field lines they may reach near the Xpoint region where the magnetic moment the first adiabatic invariant can be occasionally shifted due to a large gradient of the field. When the magnetic moment becomes large resulting in a large Larmor radius particles probabilistically cross the Xpoint to migrate to the opposite side of the TWM configuration. These phenomena are investigated with single particle simulations. We find that the statistical behaviour of the seemingly chaotic magnetic moment shifts are completely determined by the two aforementioned conserved quantities and also that there exists a threshold energy determined by the base field line value allowing only particles with a higher energy to cross the separatrix and migrate. It is found that the crossing time is distributed exponentially and that the migration confinement time which is the average crossing time is shorter for particles with a base field line closer to the separatrix and a higher energy. We provide an empirical expression derived with the simulations for estimating the collisionless migration confinement time. | 2024-03-01T00:00:00Z | ['2024JPlPh..90b9704A', '10.1017/S0022377824000321'] | ['plasma confinement', 'plasma simulation', 'plasma dynamics'] | Charged particle collisionless transport near the Xpoint of the twowire model | 2,024 | 0 | 0.1 | ['PUB_HTML', 'PUB_PDF'] | 0 | null |
2016yCat..51520088R | The initial images of HATS11 and HATS12 were obtained with the HATSouth widefield telescope network consisting of 24 Takahashi E180 astrographs with an aperture of 18cm. The photons were detected with Apogee 4k4k U16M ALTA CCDs. Details on the time span and number of images are shown in Table1. The numerical data of the light curves are available in Table3. P The spectroscopic observations are summarized in Table2. The data for the phased highprecision radial velocity and bisector span measurements are presented in Table6. P Photometric followup observations are summarized in Table1. The data are given in Table3. P 5 data files. | 2016-10-01T00:00:00Z | ['2016yCat..51520088R', '10.26093/cds/vizier.51520088'] | ['Planets', 'Stars: double and multiple', 'Photometry', 'Radial velocities'] | VizieR Online Data Catalog Spectroscopy and photometry of HATS11 and HATS12 Rabus 2016 | 2,016 | 0 | 0.1 | ['PUB_HTML'] | 0 | null |
2024PhRvD.110d4009J | We explore the idea of restoring the full diffeomorphism Diff invariance in theories with only transverse diffeomorphisms TDiff by the introduction of additional fields. In particular we consider in detail the case of a TDiff invariant scalar field and how Diff symmetry can be restored preserving locality by introducing an additional vector field. We reobtain the corresponding dynamics and energymomentum tensor from the covariantized action and analyze the potential and kinetic domination regimes. For the former the theory describes a cosmological constanttype behavior while for the latter we show that the theory can describe an adiabatic perfect fluid whose equation of state and speed of sound is obtained in a straightforward way. Furthermore the reformulation with the full symmetry allows us to analyze the gravitational properties of the theory beyond those particular regimes. In particular we find the general expression for the effective speed of sound of the nonadiabatic perfect fluid which provides us with physically reasonable conditions that should be satisfied by the coupling functions. Finally we investigate the particular models leading to an adiabatic fluid. | 2024-08-01T00:00:00Z | ['2024PhRvD.110d4009J', '10.1103/PhysRevD.110.044009'] | null | Symmetry restoration in transverse diffeomorphism invariant scalar field theories | 2,024 | 0 | 0.17 | ['PUB_HTML'] | 1 | null |
2017EGUGA..1919453E | The CassiniHuygens mission a joint collaboration between NASA ESA and the Italian Space Agency is in its last year of operations after nearly 13 years in orbit around Saturn. Cassini will send back its final bits of unique data on September 15th 2017 as it plunges into Saturns atmosphere vaporizing and satisfying planetary protection requirements. Before that time Cassini will continue its legacy of exploration and discovery in 2017 and return unique science data provided by orbits taking the spacecraft into unexplored regions near Saturn and its rings. From the new vantage points Cassini will continue to study seasonal and temporal changes in the system as northern summer solstice approaches. With the exception of one remaining targeted Titan flyby all of Cassinis close icy satellite flybys including those of Enceladus are now completed. In November 2016 Cassini transitioned to a series of orbits with peripases just outside Saturns F ring. These 20 orbits include close flybys of some tiny ring moons and excellent views of the F ring and Saturns outer A ring. The 126th and final close flyby of Titan will propel Cassini across Saturns main rings and into its Grand Finale series of orbits. Cassinis Grand Finale starting in April 2017 is comprised of 22 orbits at an inclination of 63 degrees. Cassini will repeatedly dive between Saturns innermost rings and upper atmosphere providing insights into fundamental questions unattainable during the rest of the mission. Cassini will be the first spacecraft to explore this region. These close orbits provide the highest resolution observations of both the rings and Saturn and direct insitu sampling of the ring particles composition plasma Saturns exosphere and the innermost radiation belts. Saturns gravitational field will be measured to unprecedented accuracy providing information on the interior structure of the planet winds in the outer layers of Saturns atmosphere and the mass distribution in the rings. Probing the magnetic field will give insight into the nature of the magnetic dynamo telling us why the magnetic field is weak why it exhibits little if any axial tilt and the true rotation rate of the planet. The ion and neutral mass spectrometer will sniff the exosphere and upper atmosphere for molecules that escape the atmosphere itself and waterbased molecules originating from the rings. The cosmic dust analyzer will sample the composition of particles from different parts of the main rings. Until the execution of these final orbits the answers to such new questions will remain mysteries. The science highlights of Cassinis Grand Finale orbits will be discussed. This work was carried out in part at the Jet Propulsion Laboratory California Institute of Technology under contract with NASA. Copyright 2017 California Institute of Technology. Government sponsorship is acknowledged. | 2017-04-01T00:00:00Z | ['2017EGUGA..1919453E'] | null | Cassinis Ring Grazing and Grand Finale Orbits Topping Off an Awesome Mission | 2,017 | 0 | 0 | ['PUB_PDF'] | 0 | null |
2017GCN.20364....1L | The online pycbc CBC analysis identified a candidate with GraceDB ID G268556 during processing of data from LIGO Hanford Observatory H1 and LIGO Livingston Observatory L1 at 20170104 101158.599 UTC GPS time 1167559936.599. G268556 is an event of interest because its false alarm rate as determined by preliminary analysis is less than i.e. more significant than 6.1e08 Hz about one in 6 months. The events properties can be found at this URL httpsgracedb.ligo.orgeventsG268556 Based on preliminary matchedfilter estimates of the masses and spins there is a 0 chance that the less massive companion in the binary has a mass less than 3 Msun. Based on the tidal disruption condition and disk mass formula of Foucart PRD 86 124007 using an implementation based on Pannarale amp Ohme ApJL 791 7 we estimate that there is a 0 chance that the system ejected enough neutronrich material to power an electromagnetic transient. One sky map with distance information e.g. Singer et al. 2016 ApJL 829 15 is available at this time and can be retrieved from the GraceDB event page bayestar.fits.gz an initial localization generated by the BAYESTAR pipeline. The probability is concentrated in two long thin arcs. The 50 credible region spans about 400 deg2 and the 90 region about 1600 deg2. This is the preferred sky map at this time. This event was also detected by the cWB unmodeled burst search with a sky map consistent with the one from BAYESTAR. The event candidate was not reported by the lowlatency analysis pipelines because retuning the calibration of the LIGO Hanford detector is not yet complete after the holiday shutdown. This resulted in a delay of over 4 hours before the candidate could be fully examined. We are confident that this is a highly significant event candidate but the calibration issue may be affecting the initial sky maps. We will provide an update in approximately 48 hours which may include an improved sky map. | 2017-01-01T00:00:00Z | ['2017GCN.20364....1L'] | null | LIGOVirgo G268556 Identification of a GW CBC Candidate | 2,017 | 0 | 0.1 | ['PUB_HTML'] | 0 | null |
2017GCN.20817....1D | On UT 20170304 we spectroscopically classified the following optical transient candidates LVC GCN20802 LVC GCN20791 using the Double Beam Spectrograph Oke amp Gunn 1982 on the Palomar 200inch Hale Telescope. All spectra were reduced using the pyrafdbsp pipeline Bellm amp Sesar 2016. Classification were done with SNID Blondin amp Tonry 2007 and Superfit Howell et al. 2005. Name Redshift Classification Notes iPTF17bue z0.02 SN Ia Best match is SN2005cf at 4d iPTF17buo z0 CV Consistent with LVC GCN20815 iPTF17bti z0 CV iPTF17bxa z0.076 Spectrum dominated by galaxy light iPTF17bub z0 Mdwarf flare iPTF17btx z0.022 SN II just outside 90 contour line iPTF17bvw z0.132 SN Ia Best match is SN2003du 0d iPTF17bvd Unknown Blue Featureless Spectrum iPTF17bva z0.112 SN Ia Best match is SN1990N at 7d just outside 90 contour line | 2017-03-01T00:00:00Z | ['2017GCN.20817....1D'] | null | LIGOVirgo G275697 P200DBSP Classification of iPTF Candidates | 2,017 | 0 | 0 | ['PUB_HTML'] | 0 | null |
2017GCN.21176....1P | We observed GRB 170531A Evans et al. GCN 21170 under the extended Public ESO Spectroscopic Survey for Transient Objects ePESSTO see Smartt et al. 2015 AampA 579 40 httpwww.pessto.org . The observations were performed on the ESO New Technology Telescope at La Silla with the EFOSC2 instrument in imaging mode starting from 20170531 at 231207 UT i.e. 3.1 hours from the burst. We obtained two consecutive images each one lasting 150s with the r filter. No optical afterglow is detected in the coadded image within the XRT error circle httpwww.swift.ac.ukxrtpositions down to a limiting magnitude of r gt 23 AB 3sigma c.l.. The photometric calibration was carried out assuming r17.07 AB for the star at RAJ2000 DecJ2000 080500.30 140121.3 as reported in the PANSTARRS catalogue. | 2017-06-01T00:00:00Z | ['2017GCN.21176....1P'] | null | GRB 170531A ePESSTO NTT observations | 2,017 | 0 | 0 | ['PUB_HTML'] | 0 | null |
2017GApFD.111..527Y | Using a magnetic dynamo model suggested by Kazantsev J. Exp. Theor. Phys. 1968 vol. 26 p. 1031 we study the smallscale helicity generation in a turbulent electrically conducting fluid. We obtain the asymptotic dependencies of dynamo growth rate and magnetic correlation functions on magnetic Reynolds numbers. Special attention is devoted to the comparison of a longitudinal correlation function and a function of magnetic helicity for various conditions of asymmetric turbulent flows. We compare the analytical solutions on small scales with numerical results calculated by an iterative algorithm on nonuniform grids. We show that the exponential growth of current helicity is simultaneous with the magnetic energy for Reynolds numbers larger than some critical value and estimate this value for various types of asymmetry. | 2017-11-01T00:00:00Z | ['2017GApFD.111..527Y', '10.1080/03091929.2017.1388376'] | ['Small-scale dynamo', 'Kazantsev model', 'asymptotic and numerical analysis', 'large magnetic Reynolds number'] | Magnetic helicity generation in the frame of Kazantsev model | 2,017 | 0 | 0.1 | ['PUB_HTML'] | 2 | null |
2017GCN.21510....1L | In GCN 21509 we reported the identification of a binary neutron star candidate. We had stated that actual luminosity distance to the source is likely larger than the estimated effective distance. The effective distance quoted estimates the maximum distance to the source and so the actual luminosity distance is can be smaller than the estimate of the effective distance. The BAYESTAR localization generated from H1 data only estimates an actual luminosity distance of 37 12 Mpc a posteriori mean standard deviation. The distance estimate will likely evolve with further offline followup using data from H1 L1 and V1. Analyses including data from H1 L1 and V1 are still ongoing and a skymap using gravitationalwave data will be made available as quickly as possible. GCN OPS NOTE17aug17 Per authors request the LIGOVIRGO ID was added to the beginning of the Subjectline. | 2017-08-01T00:00:00Z | ['2017GCN.21510....1L'] | null | LIGOVirgo G298048 correction to the luminosity distance reported in GCN 21509 | 2,017 | 0 | 0.12 | ['PUB_HTML'] | 0 | null |
2017GCN.21731....1B | We have observed part of the localization of the LIGOVirgo candidate G299232 during the nights 20170825 from 19h12 UT with TRE 5 fields total 80sq. deg. and TCA 5 fields total 18sq.deg.. The position of the center of the fields are reported below. Analysis is ongoing. Site RA DEC Start of the observations UT TCA 020631 403953 20170825T194350.376 TCA 020352 384817 20170825T194810.376 TCA 020921 423129 20170825T192820.376 TCA 020122 365641 20170825T195650.376 TCA 021223 442305 20170825T191250.376 TRE 020408 401200 20170825T210409.792 TRE 020024 360000 20170825T202839.792 TRE 015350 401200 20170825T203509.792 TRE 015314 360000 20170825T195939.792 TRE 015640 314800 20170825T200609.792 TRE 022607 401200 20170825T205439.792 Note TRE TAROTLa Runion TCA TAROTCalern | 2017-08-01T00:00:00Z | ['2017GCN.21731....1B'] | null | LIGOVirgo G299232 TZACTAROT observations | 2,017 | 0 | 0 | ['PUB_HTML'] | 0 | null |
2017GCN.21611....1S | We investigated serendipitous INTEGRAL observations carried out at the time of the LIGOVirgo burst candidate G298389. The satellite was pointing at RA193.46 Dec25.644 43 degrees from far from the peak of highprobability area of LIGO localization. Depending on the location within LIGO 90 confidence region the best upper limit is set by the anticoincidence shield of the spectrometer on board of INTEGRAL SPIACS IBISISGRI or IBISPICsIT. The localization of G298389 is not optimal for SPIACS observation since part of the localization it is occulted for SPIACS by the coded mask of IBIS. For harder source spectra IBIS and especially IBISPICsIT reaches sensitivity close to optimal in this orientation. The INTEGRAL IBAS automatically inspects both ISGRI Field of View and allsky SPIACS light curve. It did not reveal any significant excess above the background. We investigated the SPIACS IBISPICsIT and IBISISGRI light curves between 500 and 500 s from the trigger time 20170819 155046 UTC on temporal scales from 0.1 to 100 s and found no evidence for any significant deviation from the background. We estimate a median 3sigma upper limits in 90 LIGO localization region of 1.9e6 ergcm2 752000 keV assuming a duration of 8s and Band model parameters alpha1 beta2.5 and E peak 300 keV. To derive a limit for a typical short burst with 1 s duration we use a harder cutoff power law spectrum with a photon index of 0.5 and an Epeak 500 keV. We find a median limiting fluence of 4.0e7 ergcm2 752000 keV at 3 sigma c.l. | 2017-08-01T00:00:00Z | ['2017GCN.21611....1S'] | null | LIGOVirgo G298389 INTEGRAL search for a prompt gammaray counterpart | 2,017 | 0 | 0.06 | ['PUB_HTML'] | 0 | null |
2017GCN.21295....1H | We searched for the optical counterpart of GRB 170705A R. L. C. Starling et al. GCN Circular 21289 with the optical three color g Rc and Ic CCD cameras attached to the MITSuME 50cm telescope of Akeno Observatory Yamanashi Japan. The observation started on 20170705 112120.84 UT. We did not find any new point source within XRT circle in all three bands. We obtained following limits for the magnitudes. T0hour MIDUT TEXPsec g Rc Ic 8.59 122951 1320 gt18.5 gt17.9 gt17.8 T0 Elapsed time after the burst TEXP Total Exposure time We used GSC2.3 catalog for flux calibration. | 2017-07-01T00:00:00Z | ['2017GCN.21295....1H'] | null | GRB 170705A MITSuME Akeno Optical Observation | 2,017 | 0 | 0.1 | ['PUB_HTML'] | 0 | null |
2017GCN.21168....1G | The SwiftUVOT and XRT began settled observations of the field of GRB 170524B 120 ks after the BAT trigger Barthelmy et al. GCN Circ. 21142. A fading source consistent with the XRT position is detected in the UVOT exposures. SwiftXRT performed followup observations of the SwiftBATdetected burst GRB 170524B Barthelmy et al. GCN Circ.21142 collecting an additional 3ks 5.1 total of Photon Counting PC mode data. One uncatalogued Xray source has been detected consistent with being within 296 arcsec of the SwiftBAT position. There is also evidence of fading which is confirmed with UVOT analysis. XRT light curve can be modeled with a powerlaw decay with a decay index alpha 1.3 The preliminary UVOT position is RA J2000 060328.49 90.86872 deg. Dec J2000 170458.7 17.08297 deg. with an estimated uncertainty of 0.4 arc sec. radius 90 confidence. Preliminary detections using the UVOT photometric system Breeveld et al. 2011 AIP Conf. Proc. 1358 373 for the early exposures are Filter Tstarts Tstops Exps Mag white 120431 126833 1297 19.890.08 white 274703 286595 2027 21.110.23 The magnitudes in the table are not corrected for the Galactic extinction due to the reddening of EBV 0.19 in the direction of the burst. The decay inferred from the UVOT white data suggests a slope of approximately 1.3. This circular is an official product of the Swift team. | 2017-05-01T00:00:00Z | ['2017GCN.21168....1G'] | null | GRB 170524B SwiftUVOTXRT Confirmation of Afterglow | 2,017 | 0 | 0 | ['PUB_HTML'] | 0 | null |
2017EGUGA..1918923Q | The graphite black shale of Vendas de Ceira located in south of Coimbra Portugal caused serious instability problems in recent road excavation slopes. The problems increased with the rain transforming shales into a dark mud that acquires a metallic hue when dried. The black shales are attributed to the Devonian or eventually to the Silurian. At the base of the slope is observed graphite black shale and on the topbrown schist. Samples were collected during the slope excavation works. Undisturbed and less altered materials were selected. Further sampling was made difficult as the graphite shale was covered by a thick layer of reinforced concrete which was used to stabilize the excavated surfaces. The mineralogy is mainly constituted by quartz muscovite ilite ilmenite and feldspar without the presence of expansive minerals. The organic matter content is 0.3 to 0.4. The durability evaluated by the Slake Durability Test varies from very low Id2 of 6 for sample A to high 98 for sample C. The grain size distribution of the shale particles was determined after disaggregation with water which allowed verifying that sample A has 37 of fines 5 of clay and 32 of silt and 63 of sand while sample C has only 14 of fines 2 clay and 12 silt and 86 sand showing that the decrease in particle size contributes to reduce durability. The unconfined linear expansion confirms the higher expandability 13.4 for sample A reducing to 12.1 for sample B and 10.5 for sample C. Due the shale material degradated with water mercury porosimetry was used. While the dry weight of the three samples does not change significantly around 26 kNm3 the porosity is much higher in sample A with 7.9 of pores reducing to 1.4 in sample C. The pores size vary between 0.06 to 0.26 microns does not seem to have any significant influence in the shale behaviour. In order to have a comparison term a porosity test was carried out on the low weatherable brown shale which is quite abundant at the site. The main difference to the graphite shale is the high porosity of the brown shale with 14.7 and the low volume weight of 23 kNm3 evidencing the distinct characteristics of the graphite schists. The maximum strength was evaluated by the Schmidt hammer as the point load test could not be performed as the rock was very soft. The maximum estimated values on dry samples were 32 MPa for sample A and 85 MPa for sample C. The results show a singular material characterized by significant heterogeneity. It can be concluded that for the graphite schists the smaller particle size and higher porosity make the soft rock extremely weatherable when decompressed and exposed to water as a result of high capillary tension and reduced cohesion. They also exhibit high expansion and an enormous degradation of the rock presenting a behaviour close to a soil. The graphite black schist is a highly weatherable soft rock without expansive minerals with small pores in which the porosity low strength and low cohesion allow their rapid degradation when decompressed and exposed to the action of Water. | 2017-04-01T00:00:00Z | ['2017EGUGA..1918923Q'] | null | Graphite Black shale of Vendas de Ceira Coimbra Portugal | 2,017 | 0 | 0.22 | ['PUB_PDF'] | 0 | null |
2017GCN.20809....1C | We report the following Liverpool Telescope followup observations of EM candidates originally reported in GCN 20790. Observations were made with the SPRAT spectrograph and supernova classifications were obtained using SNID Blondin amp Tonry 2007 ApJ 666 1024. iPTF17bqh was observed on 20170302 at 2358UT. The spectrum is generally featureless with some weak hints of Balmer lines in absorption so we believe this source to be a dwarf nova in outburst. iPTF17bpt was observed on 20170303 at 0212UT. Based on a weatheraffected spectrum we classify this transient as a type Ia SN at 18 days with z0.595. | 2017-03-01T00:00:00Z | ['2017GCN.20809....1C'] | null | LIGOVirgo G275404 Liverpool Telescope classification of EM candidates | 2,017 | 0 | 0 | ['PUB_HTML'] | 0 | null |
2017GCN.21294....1E | The SwiftUVOT began settled observations of the field of GRB 170705A 82 s after the BAT trigger Starling et al. GCN Circ. 21289. We detect a fading source consistent with the XRT position Goad et al. GCN Circ. 21290 and the MASTER Lipunov et al. GCN Circ. 21291 and RATIR Butler et al. GCN Circ. 21293 detections in the initial UVOT exposures. The preliminary UVOT position is RA J2000 124648.97 191.70404 deg. Dec J2000 181826.4 18.30733 deg. with an estimated uncertainty of 0.45 arc sec. radius 90 confidence. Preliminary 3sigma upper limits using the UVOT photometric system Breeveld et al. 2011 AIP Conf. Proc. 1358 373 for the first finding chart FC exposure and subsequent exposures are Filter Tstarts Tstops Exps Mag whiteFC 82 231 147 18.55 0.06 white 573 1020 186 19.23 0.11 u 294 543 246 19.43 0.19 v 623 1070 58 gt18.3 b 549 741 39 18.92 0.26 uvw1 672 692 19 gt18.1 uvm2 4617 12950 996 gt20.7 uvw2 5644 11420 1137 gt21.0 The magnitudes in the table are not corrected for the Galactic extinction due to the reddening of EBV 0.02 in the direction of the burst Schlegel et al. 1998. | 2017-07-01T00:00:00Z | ['2017GCN.21294....1E'] | null | GRB 170705A SwiftUVOT Detection | 2,017 | 0 | 0 | ['PUB_HTML'] | 0 | null |
2024PrA....42..240X | Synthetic Aperture radar SAR which uses airplane satellites or other moving objects as the platform has the ability of allweather and alltime to observe. It has become a highly efficient method of remote sensing detection and has been widely used in various fields such as deep space exploration military reconnaissance topographic mapping disaster monitoring agricultural and forestry growth monitoring ocean current observation and other fields. This article sorts out the SAR technology status scientific objectives and detection results of several SAR systems which have been set up in deep space explorations of foreign countries and areas. And it provides comparative analysis of SAR systems including Veneras15 and 16 Magellan Cassini Chandrayaan12 and LRO. The PolSAR Polarization Synthetic Aperture Radar is carried by the Chinese lunar exploration Change7 CE7. PolSAR will lead the rapid development of Chinas deep space exploration technology. It is hoped that it can provide some help for Chinas deep space exploration in the future. At the same time the development trends of spaceborne SAR are analyzed. Spaceborne SAR is gradually moving towards highresolution multiparameters multimodes multistatic imaging lightweight and other aspects. It will eventually play a more important role in richer application fields. | 2024-06-01T00:00:00Z | ['2024PrA....42..240X', '10.3969/j.issn.1000-8349.2024.02.04'] | ['deep space exploration', 'synthetic aperture radar(SAR)', 'high resolution', 'multimode'] | Application and Development Trend of Synthetic Aperture Radar in Deep Space Exploration | 2,024 | 0 | 0.29 | ['PUB_HTML', 'PUB_PDF'] | 0 | null |
2017GCN.20808....1C | We report the following Liverpool Telescope followup observations of EM candidates originally reported in GCN 20791. Observations were made with the SPRAT spectrograph and supernova classifications were obtained using SNID Blondin amp Tonry 2007 ApJ 666 1024. iPTF17bpw was observed on 20170302 at 2220UT. The transient is centrally located within its host galaxy and the spectrum shows strong emission lines indicative of an AGN. iPTF17bou was observed on 20170302 at 2253UT. We tentatively classify this transient as a type II SN at 58 days with z0.131. | 2017-03-01T00:00:00Z | ['2017GCN.20808....1C'] | null | LIGOVirgo G275697 Liverpool Telescope classification of EM candidates | 2,017 | 0 | 0.06 | ['PUB_HTML'] | 0 | null |
2017GCN.21497....1U | We report optical followup observations for G297595 with Hyper SuprimeCam HSC 1.7 deg2 FOV attached to 8.2m Subaru Telescope. We performed Yband imaging observations of the high probability region using the updated skymap LALInference.fits on 20170816 UT. We covered about 40 deg2 with 30 pointings. Each field was visited twice with the total exposure time of 220 sec 110 sec x 2. An expected 5sigma limiting magnitude is about 23 mag AB. The observed fields are listed below. ID UT RA DEC Exp Filter 00 20170816T123225 03h19m45.9s 35d40m51.6s 110.0s HSCY 01 20170816T123446 03h16m57.2s 36d25m09.4s 110.0s HSCY 02 20170816T123707 03h14m08.5s 37d09m52.4s 110.0s HSCY 03 20170816T123927 03h11m19.8s 37d55m02.3s 110.0s HSCY 04 20170816T124148 03h19m46.0s 37d09m52.3s 110.0s HSCY 05 20170816T124408 03h16m57.3s 37d55m02.4s 110.0s HSCY 06 20170816T124629 03h14m08.6s 38d40m40.4s 110.0s HSCY 07 20170816T124850 03h11m19.9s 39d26m47.6s 110.0s HSCY 08 20170816T125111 03h08m31.2s 40d13m26.1s 110.0s HSCY 09 20170816T125332 03h05m42.5s 41d00m36.7s 110.0s HSCY 10 20170816T125553 03h19m46.1s 38d40m40.2s 110.0s HSCY 11 20170816T125815 03h02m53.8s 41d48m21.6s 110.0s HSCY 12 20170816T130035 03h16m57.4s 39d26m47.5s 110.0s HSCY 13 20170816T130257 03h14m08.7s 40d13m25.9s 110.0s HSCY 14 20170816T130518 03h00m05.2s 42d36m19.7s 110.0s HSCY 15 20170816T130739 03h11m20.0s 41d00m36.6s 110.0s HSCY 16 20170816T130959 03h08m31.3s 41d48m21.6s 110.0s HSCY 17 20170816T131220 03h05m48.0s 42d36m19.7s 110.0s HSCY 18 20170816T131441 03h19m46.2s 40d13m25.8s 110.0s HSCY 19 20170816T131702 03h16m57.5s 41d00m36.6s 110.0s HSCY 20 20170816T131923 03h02m59.4s 43d24m09.2s 110.0s HSCY 21 20170816T132144 03h14m08.9s 41d48m21.4s 110.0s HSCY 22 20170816T132404 03h00m05.3s 44d11m50.0s 110.0s HSCY 23 20170816T132625 03h11m30.9s 42d36m19.7s 110.0s HSCY 24 20170816T132846 02h57m05.4s 44d59m22.5s 110.0s HSCY 25 20170816T133106 03h08m47.8s 43d24m09.1s 110.0s HSCY 26 20170816T133328 02h53m59.3s 45d46m46.8s 110.0s HSCY 27 20170816T133549 03h05m59.4s 44d11m49.9s 110.0s HSCY 28 20170816T133810 03h17m13.7s 42d36m19.7s 110.0s HSCY 29 20170816T134031 03h03m05.4s 44d59m22.5s 110.0s HSCY 00 20170816T134259 03h19m36.4s 35d41m22.6s 110.0s HSCY 01 20170816T134520 03h16m47.6s 36d25m40.4s 110.0s HSCY 02 20170816T134741 03h13m58.8s 37d10m23.5s 110.0s HSCY 03 20170816T135001 03h11m10.0s 37d55m33.4s 110.0s HSCY 04 20170816T135222 03h19m36.3s 37d10m23.4s 110.0s HSCY 05 20170816T135443 03h16m47.5s 37d55m33.4s 110.0s HSCY 06 20170816T135704 03h13m58.7s 38d41m11.4s 110.0s HSCY 07 20170816T135925 03h11m09.9s 39d27m18.7s 110.0s HSCY 08 20170816T140146 03h08m21.1s 40d13m57.0s 110.0s HSCY 09 20170816T140407 03h05m32.3s 41d01m07.7s 110.0s HSCY 10 20170816T140630 03h19m36.2s 38d41m11.3s 110.0s HSCY 11 20170816T140851 03h02m43.5s 41d48m52.6s 110.0s HSCY 12 20170816T141112 03h16m47.4s 39d27m18.6s 110.0s HSCY 13 20170816T141334 03h13m58.6s 40d13m57.0s 110.0s HSCY 14 20170816T141555 02h59m54.6s 42d36m50.8s 110.0s HSCY 15 20170816T141817 03h11m09.8s 41d01m07.7s 110.0s HSCY 16 20170816T142038 03h08m21.0s 41d48m52.6s 110.0s HSCY 17 20170816T142259 03h05m37.5s 42d36m50.8s 110.0s HSCY 18 20170816T142520 03h19m36.1s 40d13m56.9s 110.0s HSCY 19 20170816T142741 03h16m47.3s 41d01m07.7s 110.0s HSCY 20 20170816T143002 03h02m48.8s 43d24m40.2s 110.0s HSCY 21 20170816T143223 03h13m58.5s 41d48m52.6s 110.0s HSCY 22 20170816T143444 02h59m54.5s 44d12m21.0s 110.0s HSCY 23 20170816T143705 03h11m20.4s 42d36m50.7s 110.0s HSCY 24 20170816T143926 02h56m54.4s 44d59m53.5s 110.0s HSCY 25 20170816T144148 03h08m37.2s 43d24m40.2s 110.0s HSCY 26 20170816T144408 02h53m48.3s 45d47m17.8s 110.0s HSCY 27 20170816T144629 03h05m48.6s 44d12m20.9s 110.0s HSCY 28 20170816T144850 03h17m03.2s 42d36m50.7s 110.0s HSCY 29 20170816T145111 03h02m54.4s 44d59m53.5s 110.0s HSCY | 2017-08-01T00:00:00Z | ['2017GCN.21497....1U'] | null | LIGOVirgo G297595 Subaru Hyper SuprimeCam followup observations | 2,017 | 0 | 0.1 | ['PUB_HTML'] | 0 | null |
2013APS..APRL13004L | Azimuthal anisotropy measurements are a key ingredient in ongoing efforts to pin down the precise value of the transport coefficients of the quark gluon plasma QGP produced in heavy ion collisions at both the Relativistic Heavy Ion Collider RHIC and the Large Hadron Collider LHC. I will discuss the scaling properties of these measurements and demonstrate their utility as constraints for precision extraction of several transport coefficients. | 2013-04-01T00:00:00Z | ['2013APS..APRL13004L'] | null | What do we learn from the scaling properties of azimuthal anisotropy measurements at RHIC and the LHC | 2,013 | 0 | 0 | ['PUB_HTML'] | 0 | null |
2017EGUGA..1919479P | Turbulence in stable planetary boundary layers often encountered in high latitudes influences the exchange fluxes of heat momentum water vapor and greenhouse gases between the Earths surface and the atmosphere. In climate and meteorological models such effects of turbulence need to be parameterized ultimately based on experimental data. A novel experimental approach is being developed within the COMTESSA project in order to study turbulence statistics at high resolution. Using controlled tracer releases highresolution camera images and estimates of the background radiation different tomographic algorithms can be applied in order to obtain time series of 3D representations of the scalar dispersion. In this preliminary work using synthetic data we investigate different reconstruction algorithms with emphasis on algebraic methods. We study the dependence of the reconstruction quality on the discretization resolution and the geometry of the experimental device in both 2 and 3D cases. We assess the computational aspects of the iterative algorithms focusing of the phenomenon of semiconvergence applying a variety of stopping rules. We discuss different strategies for error reduction and regularization of the illposed problem. | 2017-04-01T00:00:00Z | ['2017EGUGA..1919479P'] | null | Tomographic iterative reconstruction of a passive scalar in a 3D turbulent flow | 2,017 | 0 | 0.06 | ['PUB_PDF'] | 0 | null |
2024PhRvD.110h2009W | Timedelay interferometry TDI is a postprocessing technique used to suppress the laser phase noise for spacebased gravitational wave detectors such as TianQin by applying specific timedelay combinations to form a virtual equalarmlength interferometer. Recent studies have begun to focus on the onboard delay which is referred to as local delay in this article. Due to the stringent requirement for the laser interferometry in TianQin project the impact of local delays should be carefully studied. We show the local delays will cause nonnegligible effects on TianQins laser noise reduction for which we propose two corrections before constructing TDI variables. While the longarm delay correction has been discussed in previous studies in this research we also suggest the correction to intermediary variables or original phase measurements. As a proofofprinciple we present numerical simulation results that coincide with our analytical models and show that these corrections are valid for different TDI combinations. We find that even if the secondgeneration TDI is executed perfectly the residual laser noise is limited by the coupling of local delays and laser locking contents at high frequencies instead of the previously believed armlength mismatch of the virtual interferometer. Moreover we disucss the influence of local delays of the test mass interferometer and the reference interferometer and suggest armlength differences of the two interferometers should be equal for a more effective laser noise elimination. In addition the traditional expression of ranging bias impact should be rewritten to include additional terms for the local delays and the clock biases. Furthermore we consider a set of scenarios including six independent lasers and different laser locking configurations and find the suitable locking schemes for laser noise suppression which is proved by the simulation results. | 2024-10-01T00:00:00Z | ['2024PhRvD.110h2009W', '10.1103/PhysRevD.110.082009'] | ['Experiments in gravity', 'cosmology', 'cosmic rays'] | Timedelay interferometry with local delays for TianQin | 2,024 | 0 | 0.19 | ['PUB_HTML'] | 0 | null |
2017EGUGA..1919257I | The motion of planetary bodies their interior structure their shape and ultimately their landscape are all determined more or less directly by gravity. It is therefore not surprising that by measuring the orbital motion and the gravity field of planets and satellites we have been able to gather crucial information on the interior structure and evolution of those bodies and at the same time to put the laws of gravity to the test. Planetary geodesy is now a fully developed discipline that uses methods and observable quantities adopted also in other fields such as space navigation and telecommunications. Thanks to this winning synergy between science and engineering we can now measure spacecraft velocities to 106 ms and accelerations to 109 ms2 over time scales as short as 1000 s everywhere in the solar system. The past ten years have seen outstanding results in the scientific exploration of the deep space with gravity investigations contributing to the success of many missions. Thanks to gravity measurements MESSENGER was able to unveil the main features of Mercurys interior structure. GRAIL the first planetary mission entirely devoted to gravity recovered the structure of the lunar gravity anomalies to a spatial resolution and accuracy unmatched even for the Earth. The discovery and characterization of habitable environments in the Saturnian system on Enceladus and Titan were possible also by the radio science investigations of the mission Cassini. Thanks to a carefully designed orbit with a pericenter just 3000 km above the cloud level the spacecraft Juno is now carrying out precise gravity measurements at Jupiter to unveil the interior structure of the planet and the depth of its winds. With Cassini providing similar information at Saturn in the Grand Finale orbits just before the final plunge into the planet we will soon be able to reveal how similar or different the two gas giants are. But the interior structure of many planetary bodies remains elusive and much remains to be explored. New missions and new tools are needed. In the next five years the planetary community will see the launch of BepiColombo and JUICE two spacecraft equipped with a powerful suite of instruments devoted to the tomography of Mercury and Ganymede. Innovative instrumentation and probes are being conceived and designed. The Cassini Medal Lecture will review the past successes and future trends of planetary geodesy and radio science from the peculiar perspective of someone whose attraction for gravity kept him at the illdefined boundary between science and engineering measuring angles distances and velocities in the solar system. | 2017-04-01T00:00:00Z | ['2017EGUGA..1919257I'] | null | The Attraction of Gravity Jean Dominique Cassini Medal Lecture | 2,017 | 0 | 0.1 | ['PUB_PDF'] | 0 | null |
2018cosp...42E1652K | Clouds in planetary atmospheres can either cool or warm the climate system. Clouds provide a negative forcing to the system by increasing the planetary albedo when they reside over relatively dark surfaces. Conversely clouds provide a positive forcing to the system in the infrared where they absorb radiation and emit a fraction of it back to the surface. The net effect on the climate system depends on the relative strength of these opposing effects which depend on the cloud optical depths altitudes and particle sizes. In Earths atmosphere low clouds tend to cool the surface while high clouds tend to warm the surface. A similar effect occurs in Mars atmospherelow clouds cool while high clouds warm. Water ice clouds in Mars current atmosphere provide weak net annual warming of less than 1 Kelvin. However recent climate modeling studies suggest that water ice clouds could have provided significant greenhouse warming during Mars recent history. Even modestly increasing obliquity to 30 can produce water ice cloud greenhouse annual mean warming of 15 K. At 35 obliquity the cloudgenerated greenhouse warming can reach more than 25 K. If clouds warm Mars this significantly at moderate obliquity the planets climate could have been dominated by the effects of water ice clouds through much of its history. Given the potentially large effect of water ice clouds it is important to critically evaluate how realistic these results are. The conditions necessary for a significant cloud greenhouse depend both on microphysical processes and on the characteristics of the general circulation and transport processes. We use a Mars global climate model equipped with a stateoftheart water ice cloud microphysics package to isolate and investigate these processes to better understand the plausibility of a strong water ice cloud greenhouse in Mars recent past. | 2018-07-01T00:00:00Z | ['2018cosp...42E1652K'] | null | How plausible is an orbitdriven water ice cloud greenhouse on Mars | 2,018 | 0 | 0.06 | null | 0 | null |
2017GCN.21503....1E | Swift has performed a series of 535 observations covering 535 separate locations within the LVC error region for the GW trigger G297595 LVC Circ. 21474 convolved with the 2MPZ catalogue Bilicki et al. 2014 ApJS 210 9 using 530 fields from the bayestar GW localisation map and 5 fields from the LALInference GW localisation map. As these are 3D skymaps galaxy distances were taken into account in selecting which ones to observe. The observations currently span from 31 ks to 222 ks after the LVC trigger and cover 54.6 sq degrees on the sky corrected for overlaps. This covers 13 of the probability in the LALInference skymap and 17 after convolving with the 2MPZ galaxy catalogue as described by Evans et al. 2016 MNRAS 462 1591. Using the earlier bayestar skymap our observations covered 70 of the probability 70 when convolved. We have detected 7 Xray sources. Each source is assigned a rank of 14 which describes how likely it is to be related to the GW trigger with 1 being the most likely and 4 being the least likely. The ranks are described at httpwww.swift.ac.ukranks.php. We have found 0 sources of rank 1 0 sources of rank 2 0 sources of rank 3 7 sources of rank 4 For all flux conversions and comparisons with catalogues and upper limits from other missions we assumed a powerlaw spectrum with NH3e20 cm2 and photon index Gamma1.7 RANK 4 sources These are catalogued Xray sources showing no signs of outburst compared to previous observations so they are not likely to be related to the GW trigger. Source 1 RA 41.4741 02h 45m 53.78s J2000 Dec 44.9939 44d 59 38.0 J2000 Error 5.4 arcsec radius 90 confidence. Peak Rate 8.1e02 4.9e02 ctsec 0.310 keV Peak Flux 3.5e12 2.1e12 erg cm2 s1 0.310 keV Cat Source 1SXPS J024554.1445938 in the 1SXPS catalogue Separation 3.9 from the XRT source Cat Rate 7.9e02 4.7e03 ctsec Cat Flux 3.4e12 2.0e13 erg cm2 s1 0.310 keV so the source is not above the catalogued flux. There is no evidence for fading. NOTE this source is NOT within 200 kpc of a GWGC or 2MPZ galaxy which is consistent within 3sigma with the distance to the GW object. A SIMBAD object QSO B0244452 is 3.5 away. There is 1 2MASS object within the sources 3sigma error radius. Source 2 RA 38.6302 02h 34m 31.25s J2000 Dec 46.5331 46d 31 59.2 J2000 Error 6.3 arcsec radius 90 confidence. Peak Rate 1.1e01 5.3e02 ctsec 0.310 keV Peak Flux 4.9e12 2.3e12 erg cm2 s1 0.310 keV Cat Source XMMSL2 J023431.2463207 in the XMMNEWTONXMMSLEWCLN catalogue Separation 8.0 from the XRT source Cat Rate 9.0e01 4.3e01 ctsec Cat Flux 9.0e12 4.3e12 erg cm2 s1 0.310 keV so the source is not above the catalogued flux. The source may be fading at the 0.2sigma level. NOTE this source is NOT within 200 kpc of a GWGC or 2MPZ galaxy which is consistent within 3sigma with the distance to the GW object. A SIMBAD object 6dFGS gJ023431.3463206 is 7.3 away. There is 1 2MASS object within the sources 3sigma error radius. Source 3 RA 34.6059 02h 18m 25.42s J2000 Dec 50.2247 50d 13 28.9 J2000 Error 5.7 arcsec radius 90 confidence. Peak Rate 1.7e02 6.4e03 ctsec 0.310 keV Peak Flux 7.5e13 2.7e13 erg cm2 s1 0.310 keV Cat Source 1SXPS J021825.9501330 in the 1SXPS catalogue Separation 5.4 from the XRT source Cat Rate 2.0e02 4.1e04 ctsec Cat Flux 8.8e13 1.8e14 erg cm2 s1 0.310 keV so the source is not above the catalogued flux. There is no evidence for fading. There are 3 GWGC or 2MPZ galaxies within 200 kpc of the source. and consistent within 3sigma with the distance to the GW object. A SIMBAD object 1RXS J021824.9501335 is 7.7 away. Source 4 RA 37.5016 02h 30m 0.38s J2000 Dec 54.0222 54d 01 19.9 J2000 Error 7.8 arcsec radius 90 confidence. Peak Rate 4.6e02 1.6e02 ctsec 0.310 keV Peak Flux 2.0e12 6.7e13 erg cm2 s1 0.310 keV Cat Source 3XMM J023001.4540115 in the XMMNEWTONXMMSSC catalogue Separation 10.5 from the XRT source Cat Rate 7.9e01 1.0e02 ctsec Cat Flux 7.9e12 1.0e13 erg cm2 s1 0.310 keV so the source is not above the catalogued flux. There is no evidence for fading. NOTE this source is NOT within 200 kpc of a GWGC or 2MPZ galaxy which is consistent within 3sigma with the distance to the GW object. Source 5 RA 37.5869 02h 30m 20.86s J2000 Dec 54.2524 54d 15 08.6 J2000 Error 5.2 arcsec radius 90 confidence. Peak Rate 3.4e02 1.2e02 ctsec 0.310 keV Peak Flux 1.5e12 5.0e13 erg cm2 s1 0.310 keV Cat Source 3XMM J023021.0541506 in the XMMNEWTONXMMSSC catalogue Separation 2.3 from the XRT source Cat Rate 1.8e01 4.7e03 ctsec Cat Flux 1.8e12 4.7e14 erg cm2 s1 0.310 keV so the source is not above the catalogued flux. There is no evidence for fading. NOTE this source is NOT within 200 kpc of a GWGC or 2MPZ galaxy which is consistent within 3sigma with the distance to the GW object. There is 1 2MASS object within the sources 3sigma error radius. Source 6 RA 48.7127 03h 14m 51.05s J2000 Dec 42.0480 42d 02 52.8 J2000 Error 4.4 arcsec radius 90 confidence. Peak Rate 3.6e02 1.1e02 ctsec 0.310 keV Peak Flux 1.6e12 4.8e13 erg cm2 s1 0.310 keV Cat Source XMMSL2 J031450.4420243 in the XMMNEWTONXMMSLEWCLN catalogue Separation 11.5 from the XRT source Cat Rate 1.6e00 7.1e01 ctsec Cat Flux 1.6e11 7.1e12 erg cm2 s1 0.310 keV so the source is not above the catalogued flux. There is no evidence for fading. NOTE this source is NOT within 200 kpc of a GWGC or 2MPZ galaxy which is consistent within 3sigma with the distance to the GW object. Source 7 RA 48.4264 03h 13m 42.34s J2000 Dec 41.9943 41d 59 39.5 J2000 Error 4.9 arcsec radius 90 confidence. Peak Rate 3.5e02 1.1e02 ctsec 0.310 keV Peak Flux 1.5e12 4.6e13 erg cm2 s1 0.310 keV Cat Source 1RXS J031342.2415934 in the ROSATRASSBSC catalogue Separation 5.7 from the XRT source Cat Rate 7.9e02 1.6e02 ctsec Cat Flux 2.2e12 4.5e13 erg cm2 s1 0.310 keV so the source is not above the catalogued flux. There is no evidence for fading. There is 1 GWGC or 2MPZ galaxy within 200 kpc of the source. and consistent within 3sigma with the distance to the GW object. A SIMBAD object 2MASS J031342334159362 is 3.3 away. There is 1 2MASS object within the sources 3sigma error radius. This circular is an official product of the Swift team. | 2017-08-01T00:00:00Z | ['2017GCN.21503....1E'] | null | LIGOVirgo G297595 SwiftXRT sources | 2,017 | 0 | 0 | ['PUB_HTML'] | 0 | null |
2016xmm..prop..159M | We propose nine EPIC observations of two supergiant shells SGSsin the west of the LMC a region poorly explored in Xrays. SGSs areideal targets to find the supernova remnants and Xray binaries whichare known to be missing from current samples. We will reveal and studythe hot gas content of the SGSs and its relation with other phases ofthe interstellar medium. The Xray luminosity of the diffuse emissionwill be compared to the recent star formation rate SFR allowing tocalibrate the known relation between diffuse Xray emission and SFR overan unprecedented dynamical range. Finally an extended gammaray sourcecoincides with the surveyed regions. An Xray inventory of the targetswill provide insight into the origin of this high energy emission. | 2016-10-01T00:00:00Z | ['2016xmm..prop..159M'] | null | Exploring supergiant shells in the west of the LMC | 2,016 | 0 | 0.06 | null | 0 | null |
2016yCat..35880102B | J11080659 was observed in Aarray configuration at L and C bands on 2011 July 4 and at Xbands on 2011 July 13 under project 11A175 PI Fu. We also used HST archival observations of J11310204 and J11080659. The two sources were observed using the Wide Field Camera 3 WFC3 on board the Hubble Space Telescope HST programme code GO 12363. P 2 data files. | 2016-03-01T00:00:00Z | ['2016yCat..35880102B', '10.26093/cds/vizier.35880102'] | ['Active gal. nuclei', 'VLBI'] | VizieR Online Data Catalog VLBI images of 2 binary AGN candidates Bondi 2016 | 2,016 | 0 | 0.06 | ['PUB_HTML'] | 0 | null |
2016sros.confE..27O | Recently the SNR IC443 was detected at all nine Planck satellite frequencies Planck Collaboration Int.XXXI 2016. The characteristic dip in emissivity between around 50 to 250 GHz is observed. It is proposed to be due to a break in the synchrotron power law resulting from the injection mechanism of the energetic particles or due to cooling losses by the energetic particles. In this work different emission models that can be responsible for the particular shape of IC443 SED are tested and discussed. The possibility of spinning dust emission signatures are emphasized. | 2016-06-01T00:00:00Z | ['2016sros.confE..27O'] | null | On the shape of SNR IC443 radio to infrared continuum spectrum | 2,016 | 0 | 0 | null | 0 | null |
2024HEAD...2130005O | The Milky Way resides in a gaseous halo made up of hot and tenuous plasma. It is important to understand the physics of this gas because of its impact on the Galaxy and because it is an analog of halos of external galaxies which are currently challenging to probe. In this talk we present an absorption study of the hot Milky Way halo towards radiatively efficient and featurerich AGN NGC 4051 with 1 Ms Chandra HETG observations across two epochs 8 years apart. In contrast to typically used featureless blazars modeling Milky Way absorption here requires deblending the signal from AGN absorption. We achieve this by using an agnostic Bayesian framework and modeling Milky Way and AGN absorption fully selfconsistently using all of the data available i.e. not focusing on individual lines. Critically we consider the photoionization by the Comic Background which is relevant for this low density gas and crucially allows us to place first direct constraints on the density of the Milky Way hot halo. We also show that not considering this photoionization background biases abundance measurements. Our approach allows us now to use the deepest highest SN spectra ever taken with Chandra to map the structure of the Milky Way halo towards multiple sightlines across many visits which is important because this instrument remains the highest resolution Xray spectrograph in the soft Xray band. Full potential of this method will be enabled by future high resolution Xray missions such as e.g. LEM or Arcus. | 2024-05-01T00:00:00Z | ['2024HEAD...2130005O'] | null | Hot Milky Way halo seen in by Chandra HETG over eight years | 2,024 | 0 | 0.32 | ['PUB_HTML'] | 0 | null |
2024HEAD...2110756N | The results from recent IXPE have been suggestive that the Xrays reflected off accretion discs form an important contribution to the polarisation spectrum seen from accreting systems. I will discuss the latest work in creating Xray reflection models that include polarisation through the addition of the spectra of Stokes parameters using the XILLVER Xray radiative transfer code. This code has already produced many unpolarised Xray tables which include detailed atomic features and are regularly used in the community. I will present this work in both the context of the semianalytical calculations of Chandrasekhar 1960 and also the observations of accretion discs by IXPE over the last few years. | 2024-05-01T00:00:00Z | ['2024HEAD...2110756N'] | null | Polarised Xray Reflection Creating polarised XILLVER tables | 2,024 | 0 | 0.3 | ['PUB_HTML'] | 0 | null |
2024GeoRL..5105131M | Accurate precipitation simulations for various climate scenarios are critical for understanding and predicting the impacts of climate change. This study employs a Cyclegenerative adversarial network CycleGAN to improve global 3hraverage precipitation fields predicted by a coarse grid 200 km atmospheric model across a range of climates morphing them to match their statistical properties with those of reference finegrid 25 km simulations. We evaluate its performance on both the target climates and an independent rampedSST simulation. The translated precipitation fields remove most of the biases simulated by the coarsegrid model in the mean precipitation climatology the cumulative distribution function of 3hourly precipitation and the diurnal cycle of precipitation over land. These results highlight the potential of CycleGAN as a powerful tool for bias correction in climate change simulations paving the way for more reliable predictions of precipitation patterns across a wide range of climates. | 2024-02-01T00:00:00Z | ['10.22541/essoar.168881853.36817507/v1', '2023esoar.36817507M', '10.1029/2023GL105131', '2024GeoRL..5105131M'] | ['machine learning', 'cyclegan', 'bias correction', 'neural network', 'gan'] | Global Precipitation Correction Across a Range of Climates Using CycleGAN | 2,024 | 0 | 0.21 | ['EPRINT_HTML', 'EPRINT_PDF', 'PUB_HTML'] | 6 | null |
2016aiaw.conf..121A | It has been shown that normal radio pulsars are not distributed symmetrically relative to the plane of the Galaxy. Moreover in the directions to the Galactic center the plane of symmetry of pulsars is higher than galactic plane on average of 50pc and towards centre on average of 100pc below of this plane. Distribution of all pulsars relative to the plane of the Galaxy can be represented by an exponential function with a characteristic distance about 300pc from the galactic plane. The characteristic distance increases within 130pc420pc depending on the age of the pulsar. In the distribution of the surface density of pulsars is observed a maximum at the distances from the Galaxy centre of about 34kpc. The density of pulsars in the central region of the galaxy is about the same as in the vicinity of the sun. | 2016-09-01T00:00:00Z | ['2016aiaw.conf..121A'] | null | The Galactic distribution of Normal pulsars | 2,016 | 0 | 0.17 | null | 0 | null |
2024GeoRL..5106585V | Using observations and Atlantic forced coupled model simulations we show evidence for an asymmetry in the link between beginning of year tropical Atlantic sea surface temperature anomalies SSTAs and end of the year El NioSouthern Oscillation events. We find a greater tendency for warm Atlantic SSTAs to lead to a La Nia than for cold anomalies to lead to El Nio. The model experiments showed that the Atlantic had a greater chance to force the tropical Pacific if the Pacific was initially in a neutral state. In the model a warm Atlantic from MarchMay was able to produce an atmospheric response leading to easterly wind anomalies in the western Pacific. This in turn induces a subsurface oceanic response leading to La Nia at the end of the year. The atmospheric response does not occur for a cold Atlantic leading to no impacts in the Pacific. | 2024-02-01T00:00:00Z | ['2024GeoRL..5106585V', '10.1029/2023GL106585'] | ['pantropical', 'interbasin', 'pacemaker'] | The Tropical Atlantics Asymmetric Impact on the El NioSouthern Oscillation | 2,024 | 0 | 0.25 | ['PUB_HTML'] | 0 | null |
2024GeoRL..5108307K | Bursts of electron butterfly distributions at 10s keV correlated with chorus waves are frequently observed in the Earths magnetosphere. Strictly ducted parallel upperband chorus waves are proposed to cause them by nonlinear cyclotron trapping. However chorus waves in these events are probably nonducted or not strictly ducted. In this study testparticle simulations are conducted to investigate electron scattering driven by ducted quasiparallel and nonducted upperband chorus waves. Simulation results show butterfly distributions of 10s keV electrons can be created by both ducted and nonducted upperband chorus waves in seconds. Ducted upperband chorus waves cause these butterfly distributions mainly by accelerating electrons due to cyclotron phase trapping. However nonducted waves tend to decelerate electrons to form these butterfly distributions via cyclotron phase bunching. Our study provides new insights into the formation mechanisms of electron butterfly distributions and demonstrates the importance of nonlinear interactions in the Earths magnetosphere. | 2024-05-01T00:00:00Z | ['2024GeoRL..5108307K', '10.1029/2024GL108307'] | ['chorus wave', 'electron', 'butterfly distribution', 'nonducted', 'phase bunching', 'simulation'] | Butterfly Distributions of Energetic Electrons Driven by Ducted and Nonducted Chorus Waves | 2,024 | 0 | 0.17 | ['PUB_HTML'] | 0 | null |
2024GeoRL..5106574H | The stress redistribution from an earthquake can produce localized measurable rotations of the principal stress axes if the absolute level of differential stress in the crust is on the order of the earthquake stress drop. Two simple analytic solutions have been developed to estimate the differential stress from an observed stress rotation. However each has assumptions that may not be accurate near Earths free surface. I model synthetic earthquakes in an elastic halfspace and show that the assumptions of the methods are accurate for strikeslip earthquakes and for deep dipslip earthquakes. However they are incorrect for shallow dipslip earthquakes. I introduce a free surface correction for one of the methods for dipslip earthquakes. I revise an analysis of stress rotations due to great subduction zone earthquakes including this correction. The results support the original conclusion of near complete stress drop for many shallow subduction zone earthquakes. | 2024-02-01T00:00:00Z | ['10.1029/2023GL106574', '2024GeoRL..5106574H'] | ['stresses: crust and lithosphere', 'seismicity and tectonics', 'subduction zone processes'] | Earths Free Surface Complicates Inference of Absolute Stress From EarthquakeInduced Stress Rotations | 2,024 | 0 | 0.06 | ['PUB_HTML'] | 1 | null |
2024GeoRL..5104900J | Furans are a major class of volatile organic compounds emitted from biomass burning. Their high reactivity with atmospheric oxidants leads to the formation of secondary organic aerosol SOA including secondary brown carbon BrC that can affect global climate via interactions with solar radiation. Here we investigate the optical properties and chemical composition of SOA generated via photooxidation of furfural 2methylfuran and 3methylfuran under dry RH lt 5 and humid RH 50 conditions in the presence of nitrogen oxides NOSUBxSUB and ammonium sulfate seed aerosol. Dry furfural oxidation has the greatest BrC formation including reduced nitrogencontaining organic compounds NOCs in SOA which are dominated by amines and amides formed from reactions between carbonyls and ammoniaammonium. Based on the products detected we propose novel formation pathways of NOCs in furfural photooxidation which can contribute to BrC via accretion reactions during the photochemical aging of biomass burning plumes. | 2024-01-01T00:00:00Z | ['2024GeoRL..5104900J', '10.1029/2023GL104900'] | ['furans', 'secondary organic aerosol', 'biomass burning', 'secondary brown carbon', 'nitrogen-containing organic compounds', 'nitrogen functional groups', 'photochemical oxidation'] | Secondary Brown Carbon Formation From Photooxidation of Furans From Biomass Burning | 2,024 | 0 | 0.06 | ['PUB_HTML'] | 1 | null |
2024Gerb...21....5S | The Schwarzschild radius is implicit in the Newton equations but the general physics framework did not accept the light gravitating until the 1919 total solar eclipse of Eddington. The new spacetime vision of gravity introduced by Einstein and the progressive understanding of the stellar physics also in hyperdense conditions where the exclusion principle applies culminated in the black holes introduction of 19671971 by Wheeler and Ruffini. Black holes of stellar masses and galactic black hole from millions solar masses to billions have been observed since then with increasing resolution. The theories on their states energetics and evolution are paralleling their observations in the multimessenger era of astronomy. | 2024-04-01T00:00:00Z | ['2024Gerb...21....5S'] | ['Black Holes', 'Gravitation', 'History of Astronomy'] | Black Holes la luce che gravita | 2,024 | 0 | 0.31 | ['PUB_PDF'] | 0 | null |
2024HEAD...2110232M | We present the first selfconsistently calculated spectra from electrons accelerated in relativistic jets containing an initial toroidal magnetic field where the jets are being injected into an ambient plasma at rest. We use threedimensional relativistic particleincell calculations for different setups of plasma species strengths of the initial magnetic field Lorentz factor of the jet and emission angles. Our results show the basic properties of jitterlike spectra where the low frequency slope of the spectrum is steeper than the 13 slope of synchrotron radiation. Our calculations can be relevant for explaining the observed spectra from gammaray bursts. | 2024-05-01T00:00:00Z | ['2024HEAD...2110232M'] | null | Investigating Relativistic Jets ParticleinCell Simulations and Synthetic Spectra with Toroidal Magnetic Field Effects | 2,024 | 0 | 0.33 | ['PUB_HTML'] | 0 | null |
2024Gerb...21....1S | Coronae are photometeors formed around the Sun and the Moon because of light diffraction the angular extensions of the red rings have been measured with the help of a solar ghost image on focus to the nearest arcminute of accuracy on the day of 21 February 2024 in Rome. The determination of the pollen diameter 21.80.3 m was obtained from the photos using the formulae of Laven 2015 computed with Mie Scattering theory and angular solar diameter 0.5 16r and 31r when is measured in degrees and r in m. The first observation was under a cypress shaking a branch with open cones and this was used as calibration for the observations in the center of Rome where the corona was visible on the top of Palazzo Venezia. This was a consequence of the injection in the atmosphere of 1500 to 4500 grainsm3 100 is the threshold for intense allergy symptoms of the Cupressus Sempervirens pollens which happens in peaked occurrences and specific places and hours in the city. | 2024-02-01T00:00:00Z | ['2024Gerb...21....1S'] | ['Atmospheric Corona', 'Mie Scattering', 'Diffraction', 'Pollen', 'Optics'] | A cypress pollen solar corona observed in Rome | 2,024 | 0 | 0.24 | ['PUB_PDF'] | 0 | null |
2024FrASS..1191070D | In order to realize the realtime processing and analysis of astronomical ultrawide bandwidth signals this study proposes a subband division algorithm based on RFSoC. The algorithm uses Kaiser window to design FIR prototype lowpass filter adopts critical sampling polyphase filter bank to decompose ultrawide bandwidth signal into several subbands and encapsulates each subband into VDIF data frame and sends it to GPU server. The algorithm is implemented on RFSoC platform and its effectiveness is verified by simulation and actual observation. The experimental results show that the algorithm can divide the astronomical ultrawide bandwidth signal into multiple subbands in real time packetize and transmit them to GPU. This research provides reproducible design and project for ultrawide bandwidth signal subband division with low spectrum leakage and aliasing high data accuracy and fast processing speed. | 2024-04-01T00:00:00Z | ['2024FrASS..1191070D', '10.3389/fspas.2024.1391070'] | null | A subband division algorithm for ultrawide bandwidth pulsar signals based on RFSoC | 2,024 | 0 | 0.16 | ['PUB_HTML'] | 0 | null |
2024FrASS..1126406D | This text discusses the behavior of solutions and the energy stability within Schwarzschild spacetimes with a particular emphasis on the behavior of massless scalar fields under the influence of a nonrotating and spherically symmetric black hole. The stability of solutions in the proximity of the event horizon of black holes in general relativity remains an open question especially given the difficulties introduced by minor perturbations that may resemble Kerr solutions. To address this this work explores a simplified model including massless scalar fields to better understand perturbation behaviors around black holes under the Schwarzschild approach. We depart from Richard Prices work in connection with how scalar electromagnetic and gravitational fields behave. The tortoise coordinate transformation is considered to set the stage for numerical solutions to the wave equations. Afterward we explore energy estimates which are used to gauge stability and wave behavior over time. Our analysis reveals that the time evolution of the energy does not exceed twice its initial value. Further and under the assumption of initial conditions in L2spaces we obtain an exponential decreasing behavior in the energy time evolution. A question to continue exploring is how perturbations in L2 in the initial conditions that introduce Kerr solutions as a secondorder effect in the linearized equations perturb this obtained exponential decay. | 2024-08-01T00:00:00Z | ['2024FrASS..1126406D', '10.3389/fspas.2024.1426406'] | null | Scalar field solutions and energy bounds for modeling spatial oscillations in Schwarzschild black holes based on the ReggeWheeler equation | 2,024 | 0 | 0.16 | ['PUB_HTML'] | 0 | null |
2024FrASS..1190597B | In this brief report we present a model that complements the wellestablished canonical model for the spin evolution of rotationpowered pulsars which is typically used to estimate ages spindown luminosity and surface magnetic fields of middleaged pulsars. We analytically explore the growth of the magnetic field during a pulsars early history a period shortly after supernova explosion from which the neutron star forms encompassing the hypercritical phase and subsequent reemergence of the magnetic field. We analyze the impact of such growth on the early dynamics of the pulsar. Investigations into a pulsars magnetic evolution are not new and we expand the knowledge in this area by examining the evolutionary implications in a scenario governed by growth functions. The proposed growth functions calibrated with data from the Crab pulsar exhibit satisfactory physical behaviors. | 2024-06-01T00:00:00Z | ['10.3389/fspas.2024.1390597', '2024FrASS..1190597B'] | null | On the overall properties of young neutron stars an application to the Crab pulsar | 2,024 | 0 | 0.36 | ['PUB_HTML'] | 0 | null |
2024DPS....5621007B | Jupiters magnetic field interacts with its upper atmosphere through precipitation of energetic electrons and ions. These particles are expected to be sources of atmospheric heating and ionization. The Juno Microwave Radiometer instrument measures Jupiters thermal emission at six different frequencies. The low frequency channels are sensitive to changes in the upper atmosphere due to particle precipitation. Juno JEDI and UVS measurements provide a survey of energetic electrons ranging from keV to MeV energies. Electron precipitation of MeV electrons contributes to heating of the lower stratosphere. Additionally it causes formation of shortlived hydrocarbon ions below methane homopause. Using atmospheric models of microwave radiative transfer chemical kinetics and electron precipitation we present a comprehensive theory of Jupiters polar aurorae informed by synergistic observations from Juno. | 2024-10-01T00:00:00Z | ['2024DPS....5621007B'] | null | Juno Microwave Radiometer Observations of Jupiters Polar Aurorae | 2,024 | 0 | 0.25 | null | 0 | null |
2024DPS....5620902S | The Lucy mission is a NASA Discoveryclass mission the first mission to study asteroids in the Trojan population. It launched October 21 2021 and will fly past Trojan asteroids Eurybates Aug. 2027 Polymele Sep. 2027 Leucus Apr. 2028 Orus Nov. 2028 and the Patroclus Menoetius binary Mar. 2023. In preparation for the Trojan flybys Lucy flew past the mainbelt asteroid Dinkinesh in Nov. 2023 discovering its contact binary moon Selam Levison et al. 2024. That flyby was mainly intended as a test of the terminal tracking system used by Lucy to track its target. Lucy has another test flyby coming up on Apr. 20th 2025 the mainbelt asteroid 52246 Donaldjohanson. Donaldjohanson DJ is a small 4 km diameter Ctype asteroid in the inner main belt semimajor axis of 2.38 AU. It belongs to the Erigone collisional family which has a mean albedo of 0.051 Masiero et al. 2013. Its lightcurve is unusual with high amplitude and a long rotational period of 251 hours. It is possible that DJ may be a tumbling object or a binary system. Given our ignorance of many aspects of this asteroid the upcoming flyby should provide interesting science. The observing plan at Dinkinesh was kept simple. However the encounter sequence for DJ is designed to be a test of the full complexity of the planned Trojan encounter sequences packed with more observations and taking more data volume. The current Polymele encounter sequence was used as the basis for the DJ sequence. Lucy will fly past DJ at 13.4 kms with a CA distance of 960 km giving the same angular rate of motion as the Polymele flyby. We will move the Instrument Pointing Platform away from the asteroid at about 40 seconds before close approach to prevent pointing the instruments too close to the sun. Additionally due to DJs small heliocentric distance we will point the instruments away from DJ from E9 hours to E40 minutes to keep the nearIR imaging spectrometer LEISA cool so that it can provide good data near close approach. During the encounter the highresolution LLORRI camera will obtain panchromatic imaging of DJ down to 5.5 mpixel and the MVIC camera will obtain color imaging down to 83 mpixel. The LEISA instrument will obtain spectroscopic images covering a 1.03.8 m spectral range down to 345 mpixel and covering 42.3 m at about 88 mpixel. The TES instrument will take diskintegrated thermal measurements. | 2024-10-01T00:00:00Z | ['2024DPS....5620902S'] | null | The Lucy Missions Upcoming Flyby of Asteroid 52246 Donaldjohanson | 2,024 | 0 | 0.32 | null | 0 | null |
2024E&ES.1371f2035A | The objective of this research was to find out how digestible six different pelleted fish diets were in terms of dry matter and protein. Using chromium dioxide as an inert biomarker the six pretreatment diets were tested on the performance of common carp fingerlings. Treatment T1 included commercial fishmeal and treatment T2 did not contain fish offal meal supported with commercial protease enzyme. Treatments 3 4 5 and 6 all contained fish offal meal supported with protease enzyme in proportions of 1.5 2 2.5 and 3 respectively. The experimental diets were designed to have the same amount of calories and protein. Chromium concentrations proximate components of test diets and feces were also calculated. T4 had the highest ADC for dry matter DM at 86.43 while T3 had the lowest at 73.35 according to the results. The ADCs values for crude protein content were also highest in T4 91.92 and lowest in T3 80.20. According to the research common carp can maximize their nutritional digestion with the help of used fish offal meal and up to 1.5 protease enzymes in their diet. | 2024-07-01T00:00:00Z | ['10.1088/1755-1315/1371/6/062035', '2024E&ES.1371f2035A'] | ['Digestibility coefficients', 'Common carp', 'Fish offal meal', 'Diets', 'Protease enzyme'] | Effect of Fish Offal Meals as Animal Protein on Digestibility of Common Carp cyprinus carpio L. | 2,024 | 0 | 0.19 | ['PUB_HTML'] | 0 | null |
2024DPS....5640104S | The Rosetta spacecraft collected unprecedented abundant data of comet 67P by insitu and remote sensing measurement while it was orbiting the comet during the mission from 2014 to 2016. Using a wellestablished inversion model Combi et al 2020 and the measurements from the ROSINA MIRO and VIRTIS we are able to derive the surface activity distributions of various species H2O CH4 NH3 HCN etc. for a given period of time. The surface activity maps provide the boundary conditions on the nucleus surface in a kinetic coma model based on the Direct simulation Monte Carlo DSMC method. With the corresponding solar location relative to the comet at any given time the model can produce the gas density velocity and temperature distributions anywhere in the coma. Upon returning in 2021 highresolution nearinfrared groundbased spectroscopic observations of comet 67P near perihelion were conducted from the W. M. Keck Observatory which offers information of spatial distributions and rotational temperature profiles of various species extending the Rosetta measurements from the previous orbit. The comparison between the coma model driven by Rosetta data and the largerscale groundbased nearIR observations will help us evaluate possible evolution or lack thereof in outgassing patterns between the 2015 and 2021 nearperihelion passages. Preliminary results will be presented. This work is supported by NASA grants 80NSSC20K0651 from the Solar System Working program and 80NSSC22K1064 from the Discovery Data Analysis Program. | 2024-10-01T00:00:00Z | ['2024DPS....5640104S'] | null | Comparison between new groundbased observations in 2021 and a coma model driven by Rosetta data of comet 67P | 2,024 | 0 | 0.44 | null | 0 | null |
2024DPS....5620604B | The NASA Europa Clipper mission 1 will explore Jupiters icy moon Europa via multiple flybys in the early 2030s. Europa is one of the most promising locations to search for life elsewhere in the Solar System 2 3 4 5 and thus Europa Clippers main goal is to characterize Europas habitability. In the future a followon landed mission may possibly explore Europa from its surface. In our science team the Reconnaissance Focus Group has been assessing the trajectory for opportunities 6. Here we show that 12 of the 49 currently planned flybys for the prime mission of Europa Clipper 7 survey at least one area where the fundamental requirements for terrain relative navigation TRN are fulfilled. We call them reconable. P What is a reconable flyby P A reconable flyby contains at least one section where the following fundamental i.e. architecture independent requirements for terrain relative navigation TRN are fulfilled as based on current technology 8 9 P Time of day the data must be taken during the Europan day i.e. lit by sunlight P Incidence angle of data 30 60 for TRN process to be successful 20 30 may be usable in some instances but there is a rapid degradation above 60. P Altitude 50100 km for sufficiently high spatial resolution data with minimal smearing. 100105 km altitude may be useable in some instances. P Thus only 12 of the 49 flybys are reconable. P In a nutshell P Reconable flybys are relatively rare. Its important to recognize that this current assessment is limited by the data available. Rankings will probably evolve but this work demonstrates the process that can be used by the Europa Clipper team to assess potential landing sites. P The results of this work will be integrated in the science input provided for observation planning. P Acknowledgements P This work was supported by the Europa Clipper Project. The research described in this manuscript was carried out at the Jet Propulsion Laboratory California Institute of Technology under a contract with the National Aeronautics and Space Administration. Our team would also like to acknowledge the work from the Galileo instrumental teams and the PDS imaging node for making this data publicly available. P References P 1 Howell amp Pappalardo Nature Comm 2020 2 Pappalardo et al. JGR Planets 1999 3 Carr et al. Nature 1998 4 Vance et al. JGR Planets 2018 5 Cockrell et al. Astrobiology 2016 6 Phillips et al. PSJ in revision 7 Pappalardo et al. SSR 2024 8 Johnson et al. AIAA Guidance Navigation and Control Conference 2015 9 Neleseen et al. IEEE Aerospace Conference 2019 10 Turtle et al. SSR under review. | 2024-10-01T00:00:00Z | ['2024DPS....5620604B'] | null | Potential landing sites to be surveyed by Europa Clipper | 2,024 | 0 | 0.19 | null | 0 | null |
2015AAS...22521006X | Recent gamma ray observations show that middle aged supernova remnants interacting with molecular clouds can be sources of both GeV and TeV emission. Models involving reacceleration of preexisting cosmic rays in the ambient medium and direct interaction between supernova remnant and molecular clouds have been proposed to explain the observed gamma ray emission. For the reacceleration process standard DSA theory in the test particle limit produces a steady state particle spectrum that is too flat compared to observations which suggests that the high energy part of the observed spectrum has not yet reached a steady state. We derive a time dependent DSA solution in the test particle limit for situations involving reacceleration of preexisting cosmic rays in the preshock medium. Simple estimates with our time dependent DSA solution plus a molecular cloud interaction model can reproduce the overall shape of the spectra of IC 443 and W44 from GeV to TeV energies through pure 0decay emission.We allow for a power law momentum dependence of the diffusion coefficient finding that a power law index of 0.5 is favored. | 2015-01-01T00:00:00Z | ['2015AAS...22521006X'] | null | TimeDependent Diffusive Shock Acceleration in Slow Supernova Remnant Shocks | 2,015 | 0 | 0 | null | 0 | null |
2024FrASS..1196527F | It has been shown that a proxy determination of the magnetospheric openclosed magnetic field line boundary OCB location can be made by examining the ultralowfrequency ULF wave power in magnetometer data with particular interest in the Pc5 ULF waves with periods of 310 min. In this study we present a climatology of such Pc5 ULF waves using groundbased magnetometer data from the South Pole Station SPA McMurdo MCM station and the Automatic Geophysical Observatories AGOs located across the Antarctic continent to infer OCB behavior and variability during geomagnetically quiet times i.e. Ap lt 30 nT. For each season i.e. austral fall 20 February 201720 April 2017 austral winter 20 May 201720 July 2017 austral spring 20 August 201720 October 2017 and austral summer 20 November 201720 January 2018 northsouth i.e. Hcomponent magnetic field line residual powerspectral density PSD measurements taken during geomagnetically quiet periods within a 60day window centered at the austral solsticeequinox are averaged in 10min temporal bins to form the climatology at each station. These residual PSDs thus enable the analysis of Pc5 activity and lower period longband oscillations and thus OCB locationvariability as a function of season and magnetic latitude. The dawn and dusk transitions across the OCB are analyzed with a discussion of dawn and dusk variability during nominally quiet geomagnetic periods. In addition latitudinal dependencies of the OCB and peak Pc5 periods at each station are discussed along with the empirical Tsyganenko model comparisons to our site measurements. | 2024-08-01T00:00:00Z | ['2024FrASS..1196527F', '10.3389/fspas.2024.1396527'] | null | Climatology of the openclosed boundary using ULF wave observations from South Pole McMurdo and distributed Antarctic AGOs | 2,024 | 0 | 0.21 | ['PUB_HTML'] | 0 | null |
2016SPIE10154E..1RL | Freeform system theory and its influence on aberration and control is the basis to develop such a system design which has application value in engineering aspects. The principle approach modeling and error analysis are analyzed and the system configuration based on freeform is advanced in algorithm analysis. | 2016-10-01T00:00:00Z | ['10.1117/12.2247073', '2016SPIE10154E..1RL'] | null | On freeform configuration to control system aberrations | 2,016 | 0 | 0 | ['PUB_HTML'] | 0 | null |
2024FrASS..1020081S | This paper develops the stellar interior geometry for charged anisotropic spherical matter distribution by developing an exact solution of the field equations of Rastall gravity using the notion of gravitational decoupling. The main purpose of this investigation is the extension of the wellknown isotropic model within the context of charged isotropic Rastall gravity solutions. The second aim of this work is to apply gravitational decoupling via a minimal geometric deformation scheme in Rastall gravity. Finally the third one is to derive an anisotropic version of the charged isotropic model previously obtained by applying gravitational decoupling technology. We construct the field equations which are divided into two sets by employing the geometric deformation in radial metric function. The first set corresponds to the seed charged isotropic source while the other one relates the deformation function with an extra source. We choose a known isotropic solution for spherical matter configuration including electromagnetic effects and extend it to an anisotropic model by finding the solution of the field equations associated with a new source. We construct two anisotropic models by adopting some physical constraints on the additional source. To evaluate the unknown constants we use the matching of interior and exterior spacetimes. We investigate the physical feasibility of the constructed charged anisotropic solutions by the graphical analysis of the metric functions density pressure anisotropy parameter energy conditions stability criterion mass function compactness and redshift parameters. For the considered choice of parameters it is concluded that the developed solutions are physically acceptable as all the physical aspects are wellbehaved. | 2024-01-01T00:00:00Z | ['10.3389/fspas.2023.1320081', '2024FrASS..1020081S'] | null | Gravitationally decoupled charged anisotropic solutions in Rastall gravity | 2,024 | 0 | 0.21 | ['PUB_HTML'] | 4 | null |
2024GeoRL..5108961A | Uranus is one of the least explored planets in our solar system it exhibits a unique magnetic field structure which was observed by NASAs Voyager 2 mission nearly 50 years ago. Notably Uranus displays extreme magnetic field asymmetry a feature exclusive to the icy giants. We use the Boris algorithm to investigate how high energy protons behave within this unusual magnetic field which is motivated by Voyager 2s observation of lowerthanexpected high energy proton radiation belt intensities at Uranus. When considering full drift motions of high energy protons around Uranus the azimuthal drift velocity can vary by as much as 15 around the planet. This results in areas around Uranus where particles will be more depleted faster drift and other regions where there is a surplus of particles slower drift. This could provide a partial explanation for the weak proton radiation belts observed by Voyager 2. | 2024-06-01T00:00:00Z | ['10.1029/2024GL108961', '2024GeoRL..5108961A'] | ['Uranus', 'radiation belts', 'planetary magnetic field', 'drift velocity'] | Asymmetry in Uranus High Energy Proton Radiation Belt | 2,024 | 0 | 0.27 | ['PUB_HTML'] | 1 | null |
2016cosp...41E2094Y | A combination of intact capture and insitu detection of organic molecules from extraterrestrial environments is a key step towards understanding the variety and distribution of the building blocks of life other than the terrestrial one. The best candidate in terms of technical feasibility of our time is to sample currently ejecting icy plumes of the Satruns satellite Enceladus. While gas chromatographymass spectrometry GCMS has been dominantly used as successful and robust organic detection system in space it is not suited for the separation and detection of nonvolatile heatdegradable organic molecules. Using polypeptides as a candidate molecule target we we able to separate 16 out of the 17 tripeptides consisting of abiotically available amino acids by using capillary electrophoresis CE. This can be regarded an example of possible biosignatures that can be found in habitable extraterrestrial environments such as deep habitats of internal oceans of satellites of gas giants like Enceladus. We further used these peptides for the simulated Enceladus sample return using hypervelocity impact experiment facility at the same encountering velocity i.e. 46 kms as flying through sampling mission to its plumes like the LIFE mission concept. As a result by using the spaceproven 0.01gcc aerogels two peptide peaks corresponding to negatively charged peptides were detected thus representing a full simulation of the capture extraction and analysis of peptides from plume particles. Since the aerogel module is crushable and can be soaked with the electrophoresis agentssolutions and injected to capillary this media can be used for insitu wet analysis in addition to previously known usage for sample return missions. | 2016-07-01T00:00:00Z | ['2016cosp...41E2094Y'] | null | Intact Capture and Insitu Analysis System for Possible Biomarkers of Enceladus Plume Particles | 2,016 | 0 | 0.17 | null | 0 | null |
2016cxo..prop.5021K | We propose to observe a complete sample of 4 galaxy clusters at 1e14 lt M500 lt 3e14 and 0.8 lt z lt 0.9. These systems were selected from the 100 deg2 deep field of the SPTPol SZ survey. This survey are has significant complementary data including uniform depth ATCA Herschel Spitzer and DES imaging enabling a wide variety of astrophysical and cosmological studies. This sample complements the successful SPTXVP survey which has a broad redshift range and a narrow mass range by including clusters over a narrow redshift range and broad mass range. These systems are such low mass and high redshift that they will not be detected in the eRosita allsky survey. | 2016-09-01T00:00:00Z | ['2016cxo..prop.5021K'] | null | A Chandra Survey of lowmass clusters at 0.8 lt z lt 0.9 selected in the 100 deg2 SPTPol Deep Field | 2,016 | 0 | 0 | null | 0 | null |
2016csss.confE.151S | The 388nm CN band like the better known G band of CH is used in the Sun to locate strong magnetic concentrations. Magnetic network and plage are bright in these molecular bands since the enhanced chromospheric heating there destroys the molecule erasing its absorption and allowing the continuum to shine through. We take advantage of this to estimate the filling factor of strong fields in active dwarf stars. CN band depths in active stars can be compared with those of inactive stars of very similar temperature and metallicity and after an adjustment for lineblanketing used to estimate a magnetic plage filling factor. We estimate filling factors for a two stars and compare them to direct Stokes I linebroadening measurements. Limitations caveats and future directions are briefly considered. | 2016-12-01T00:00:00Z | ['10.5281/zenodo.231291', '2016csss.confE.151S'] | ['Magnetic fields', 'Cool Stars', 'Zenodo community cs19'] | Estimates Of Magnetic Plage Filling Factors Using The Cn Band | 2,016 | 0 | 0.12 | ['PUB_HTML'] | 0 | null |
2016usc..confE.115C | Sunquake events are transient acoustic emissions caused by solar flares. Many past efforts have used helioseismic holography method which employs a theoretical Greens Function for quiet Sun to reconstruct acoustic sources caused by flares. In this work rather than a theoretical Greens Function based on a quietSun model we use an observational Greens Function constructed from timedistance measurements of outgoing waves from sunspots regions to reconstruct acoustic emissions during solar flares. This is expected to give a betterdetermined sunquake location and timing. We apply this newly developed analysis method on 50 strongest solar flares observed by the SDOHMI during the solar cycle 24 and study both the temporal and spatial relations among sunquake events whitelight enhancements and Dopplervelocity anomalies caused by the flares. Based on these studies we discuss what causes sunquake events and why only a small fraction of flares are associated with sunquakes. | 2016-10-01T00:00:00Z | ['2016usc..confE.115C'] | ['SDO', 'SDO 2016', 'Solar Dynamic Observatory', 'SDO-2016', 'SDO Workshop', "SDO 2016: Unraveling the Sun's Complexity"] | A Survey of Sunquake Events in Solar Cycle 24 | 2,016 | 0 | 0.17 | ['PUB_HTML'] | 0 | null |
2014AGUFM.P42A..04C | The Balloon Observation Platform for Planetary Science BOPPS mission is a stratospheric balloon mission to conduct planetary science observations during a oneday flight from Ft. Sumner NM in late September 2014. BOPPS will fly an 80cm telescope with two instruments to detect and characterize two Oort Cloud comets C2013 A1 Siding Spring and C2012 K1 PanSTARRS. The BOPPS instruments 12 are the BOPPS Infrared Camera BIRC imaging at R band and from 2.5 to 5 microns and the UVvis camera which includes a fine pointing system to demonstrate subarc second pointing and ability to obtain high SNR imaging at wavelengths near 300 nm sensitive to OH emission 1. The BIRC will image the comets in nine filter pass bands at 1.16 arc second per pixel resolution and will measure the strengths of H2O and CO2 emissions at 2.7 and 4.3 respectively. These are the primary volatiles driving cometary activity and there is no alternative way to make these measurements from Earth or from space. The BIRC observations of Comet Siding Spring will occur about three weeks prior to the close approach of the comet to Mars which will also be observed by the full constellation of Mars spacecraft. We will report initial results of BOPPS comet observations. References 1 Young EF et al. 2014 Fall AGU this session 2 Hibbitts et al. 2014 Fall AGU | 2014-12-01T00:00:00Z | ['2014AGUFM.P42A..04C'] | ['4305 Space weather', 'NATURAL HAZARDS', '6005 Atmospheres', 'PLANETARY SCIENCES: COMETS AND SMALL BODIES', '6022 Impact phenomena', 'PLANETARY SCIENCES: COMETS AND SMALL BODIES', '6023 Comets: dust tails and trails', 'PLANETARY SCIENCES: COMETS AND SMALL BODIES'] | BOPPS Observations of Oort Cloud Comets Siding and PanSTARRS | 2,014 | 0 | 0 | null | 0 | null |
2016csss.confE.143M | Linear polarization due to scattering processes can be used as a probe of the existence of atmospheric condensates in ultracool dwarfs. Models predict that the observed linear polarization increases with the degree of oblateness which is inverse to the surface gravity.We aimed to measure optical linear polarization from a sample of six young brown dwarfs with spectral types between M6 to L2 and cataloged previously as objects with low gravity using spectroscopy. These targets are believed to have dusty atmospheres as a consequence of their low gravity therefore linearly polarized light is expected from these objects.Linear polarimetric data were collected in I and Rband using CAFOS at the 2.2m telescope in Calar Alto Observatory.We obtained results of linear polarization in the Iband compatible with non polarization for all the objects and similar results for the polarization degree in the Rband for all objects with the exception of 2M0422. For this object we find a linear polarization degree of 0.810.18. 2M0422 is 10 deg to the south of the Taurus starforming region thus we suspect that its polarization is caused by the dust in the cloud in which 2M0422 might be embedded. | 2016-08-01T00:00:00Z | ['2016csss.confE.143M', '10.5281/zenodo.59470'] | ['Zenodo community cs19'] | Polarization of Young Brown Dwarfs | 2,016 | 0 | 0.18 | ['PUB_HTML'] | 0 | null |
2016cosp...41E2171Z | The Dark Matter Particle Explorer DAMPE Chinese first high energy cosmic ray explorer in space has been successfully launched at Jiuquan Satellite Launch Center with the mission of searching dark matter particle. Large energy range for electrongamma good energy resolution and excellent PID ability make DAMPE to be the most promising detector so far to find the signal of dark matter. DAMPE consists of four subdetectors Plastic Scintillation detector SiliconTungsten tracker BGO calorimeter and Neutron detector. The hit signals generated by the BGO calorimeter and the trigger board in DAQ constitute the trigger system of DAMPE which will generate trigger signals for the four subdetectors to start data acquisition. The trigger system reduces the trigger rates on orbit from about 1kHz to 70100Hz that releases the stress of DAQ transmitting data to ground. In this paper we will introduce the trigger system of DAMPE and present some preliminary onorbit results e.g. trigger efficiency together with the beam test results at CERN and the simulation results as comparison. | 2016-07-01T00:00:00Z | ['2016cosp...41E2171Z'] | null | Preliminary onorbit results of trigger system for DAMPE | 2,016 | 0 | 0.12 | null | 0 | null |
2016cosp...41E2170Z | The scientific object of Dark Matter Particles ExplorerDAMPE is the measurement of electrons and photons in the range of 5GeV10TeV and the flux of nuclei up to 500TeV with excellent resolution and the realization of measurements will identify possible Dark MatterDM signature and help deepen our understanding of the origin and propagation of high energy cosmic ray respectively. Plastic Scintillator Detector Array PSD which adopts perpendicular structure with two layers and each layer consists of 15 scintillator strips is one subdetector of DAMPE for detecting heavy ions and distinguishing photons and electrons. In this paper the design and some test results of PSD are to be described. | 2016-07-01T00:00:00Z | ['2016cosp...41E2170Z'] | null | Development of the Plastic Scintillator Detector Array for the Prototype of the Dark Matter Particle Explorer | 2,016 | 0 | 0.1 | null | 0 | null |
2016gac..conf..352G | Years of research have shown that all experimentally obtained time series of the electric and geomagnetic fields have components at frequencies infra low frequency gravitationalwave emission of a number of binary star systems J 07006418 J 10125307 J 15371155 J 19592048 J 21301210 J 1915160 with effective values 028 06 Vm. It is shown that all reviewed time series have noncoherent components on the axion frequency 5e6 Hz with effective values of 071 136 Vm and also at combination frequencies of this frequency with the frequency of the moon tides... | 2016-01-01T00:00:00Z | ['10.1142/9789814759816_0076', '2016gac..conf..352G'] | null | Electromagnetic field of the Earth as a tool for astrophysical processes investigations | 2,016 | 0 | 0 | ['PUB_HTML', 'PUB_PDF'] | 0 | null |
2016csss.confE.112S | Activity cycles are commonly found among late type stars through the chromospheric Ca II emission. Their coronal counterpart however remains elusive in most cases despite of the clear Xray cycle observed in the solar corona spanning as much as 1.7 dex in L x . The recent discovery of a Ca II cycle in iota Hor of just 1.6 yr the shortest to date offered us a unique opportunity to monitor its Xray counterpart in short time.BR The star offers also two more interesting properties a planet of 1.9 MSUBJSUB orbits the star at 0.9 a.u. and with an age of only 600 Myr and spectral type F8V Hor represents a young solar analog so its cycle might be the paradigm of the first activity cycles in the life of a solarlike star. Our XMMNewton observations show the first coronal cycle in a single star. In good agreement with Ca II contemporaneous observations the long term XMMNewton light curve suggests also a longterm trend that seems to modulate the 1.6 yr cycle. Iota Hor may offer us the unique possibility to observe for the first time a double coronal cycle similar to those observed in the chromosphere of other stars. | 2016-07-01T00:00:00Z | ['10.5281/zenodo.59043', '2016csss.confE.112S'] | ['activity cycles', 'stellar coronae', 'astrobiology', 'planetary systems', 'Zenodo community cs19'] | Evidence For A Double Coronal Cycle In The Young Solar Analog Iota Hor | 2,016 | 0 | 0.1 | ['PUB_HTML'] | 2 | null |
2016cosp...41E1097L | Discussion | 2016-07-01T00:00:00Z | ['2016cosp...41E1097L'] | null | Discussion | 2,016 | 0 | 0 | null | 0 | null |
2016cosp...41E1756S | 4U 162667 is an ultracompact binary pulsar with a pulse period of 7.7 sec and an orbital period of 40 min. Its Xray spectrum varies distinctively before and after torque reversal episodes. 4U 162667 is a peculiar ultracompact binary in that it not only truncates its accretion disk at the magnetospheric radius but also emits Ne and O Doppler Xray lines The nature of these lines have remained quite mysterious but we can now show that these lines originate from a coronal type plasma with temperatures up to 10 Million degrees located at the magnetospheric radius. The disk line fits constrain the source distance to about 5 kpc. We also observe consistent variations in the disk lines before and after torque reversal. The observed disk lines constrain the angle of inclination to 38 degrees which is is significantly larger than previously assumed. We discuss these findings in the context of accreting Xray binaries and binary pulsar properties. | 2016-07-01T00:00:00Z | ['2016cosp...41E1756S'] | null | Hot Collionsal Plasma Emissions in the Ultracompact Binary Pulsar 4U 162667 | 2,016 | 0 | 0 | null | 0 | null |
2016cosp...41E1752S | Space radiation risk assessment is of great importance for manned spaceflights in order to estimate risks and to develop countermeasures to reduce them. Biophysical simulations with PARTRAC can help greatly to improve the understanding of initial biological response to ionizing radiation. Results from modelling radiation quality dependent DNA damage and repair mechanisms up to chromosomal aberrations e.g. dicentrics can be used to predict radiation effects depending on the kind of mixed radiation field exposure. Especially dicentric yields can serve as a biomarker for an increased risk due to radiation and hence as an indicator for the effectiveness of the used shielding. PARTRAC 1 is a multiscale biophysical research MC code for track structure based initial DNA damage and damage response modelling. It integrates physics radiochemistry detailed nuclear DNA structure and molecular biology of DNA repair by NHEJpathway to assess radiation effects on cellular level 2. Ongoing experiments with quasihomogeneously distributed compared to submicrometre focused bunches of protons lithium and carbon ions allow a separation of effects due to DNA damage complexity on nanometre scale from damage clustering on sub micrometre scale 3 4. These data provide an unprecedented benchmark for the DNA damage response model in PARTRAC and help understand the mechanisms leading to cell killing and chromosomal aberrations e.g. dicentrics induction. A large part of space radiation is due to a mixed ion field of high energy protons and few heavier ions that can be only partly absorbed by the shielding. Radiation damage induced by lowenergy ions significantly contributes to the high relative biological efficiency RBE of ion beams around Bragg peak regions. For slow light ions the physical cross section data basis in PARTRAC has been extended to investigate radiation quality effects in the Bragg peak region 5. The resulting range and LET values agree with ICRU data and SRIM calculations. Preliminary studies regarding the biological endpoints DSB cluster and chromosomal aberrations have been performed for selected light ions up to neon. Validation with experimental data as well as further calculations are underway and final results will be presented at the meeting. Mitochondrial alterations have been implicated in radiationinduced cardiovascular effects. To extend the applicability of PARTRAC biophysical tool towards effects on mitochondria the nuclear DNA and chromatin as the primary target of radiation has been complemented by a model of mitochondrial DNA mtDNA to mimic a coronary cell with thousand mitochondria contained in the cytoplasm. Induced mtDNA damage SSB DSB has been scored for 60Co photons and 5 MeV alphaparticle irradiation assuming alternative radical scavenging capacities within the mitochondria. While direct radiation effects in mtDNA are identical to nuclear DNA indirect effects in mtDNA are in general larger due to lower scavenging and the lack of DNAprotecting histones. These simulations complement the scarce experimental data on radiationinduced mtDNA damage and help elucidate the relative roles of initial mtDNA versus nuclear DNA damage and of pathways that amplify their respective effects. Ongoing and planned developments of PARTRAC include coupling with a radiation transport code and trackstructure based calculations of cell killing for RBE studies on macroscopic scales within a mixed ion field. 1 Friedland Dingfelder et al. 2011 Track structures DNA targets and radiation effects in the biophysical Monte Carlo simulation code PARTRAC Mutat. Res. 711 2840 2 Friedland et al. 2013 Track structure based modelling of chromosome aberrations after photon and alphaparticle irradiation Mutat. Res. 756 213223 3 Schmid Friedland et al. 2015 Submicrometer 20 MeV protons or 45 MeV lithium spot irradiation enhances yields of dicentric chromosomes due to clustering of DNA doublestrand breaks Mutat. Res. 793 3040 4 Friedland Schmitt Kundrat 2015 Modelling Proton bunches focussed to submicrometre scales LowLET Radiation damage in highLETlike spatial structure Radiat. Prot. Dosim. 166 3437 5 Schmitt Friedland Kundrat Dingfelder Ottolenghi 2015 Cross section scaling for track structure simulations of lowenergy ions in liquid water Radiat. Prot. Dosim. 166 1518 Supported by the European Atomic Energy Communitys Seventh Framework Programme FP720072011 under grant agreement no 249689 DoReMi and the German Federal Ministry on Education and Research KVSFProjekt LETVerbund. | 2016-07-01T00:00:00Z | ['2016cosp...41E1752S'] | null | Track structure based modelling of light ion radiation effects on nuclear and mitochondrial DNA | 2,016 | 0 | 0.06 | null | 0 | null |
2016eMetN...1...27R | One of the first meteors captured on the new camera 394 installed in Dourbes Belgium proved to be simultaneously with two other stations Mechelen Belgium camera 390391 and Oostkapelle the Netherlands camera 339. This meteor displayed a remarkable end flare of about magnitude 4. | 2016-01-01T00:00:00Z | ['2016eMetN...1...27R'] | null | A peculiar meteor recorded by CAMSBenelux on 29 February 2016 | 2,016 | 0 | 0.06 | ['ADS_PDF', 'ADS_SCAN'] | 0 | null |
2024FrASS..1103154M | This study investigates the downward motion of Intermediate EF Layers ILs in the Brazilian low latitude sector through observation and modeling. Ionosonde data from So Jos dos Campos SJC and Palmas PAL were analyzed to investigate the seasonal variation of the IL parameters including the virtual height hIL and the top frequency ftIL. The ILs primarily originated from F layer detachment followed by downward motion peaking before 11 LT and disappearing well before sunset. Daily height variability ranged between 130 and 190 km with peak frequencies around 45 MHz. Using meteor radar data as input the Ionospheric Eregion Model MIRE simulated diurnal and semidiurnal tides to analyze neutral wind effects on ILs descent. Model simulations for SJC October 2008 and PAL April and June 2009 revealed distinct wind oscillations influencing IL dynamics at heights below 140 km. In SJC meridional wind shears controlled IL descent with possible zonal wind interactions weakening ILs. Conversely in PAL during April 2009 both zonal and meridional winds contributed to IL formation and altitude descent. However discrepancies between observed and modeled descent rates suggest the need for considering additional atmospheric wave interactions in future modeling studies. June 2009 over PAL presented unique IL behavior exhibiting a lower observed decay rate and daily height oscillations potentially linked to local modulations. Meanwhile MIRE indicated that meridional wind shearing predominantly controlled IL descent in the morning with zonal wind becoming relevant postmidday. These findings enhance our understanding of IL dynamics and their atmospheric drivers. | 2024-07-01T00:00:00Z | ['10.3389/fspas.2024.1403154', '2024FrASS..1103154M'] | null | Intermediate EF layer dynamics study in the Brazilian lowlatitude sector observational data and simulations | 2,024 | 0 | 0.14 | ['PUB_HTML'] | 0 | null |
2024FrASS..1103135D | Introduction The properties of the Sbursts observed during the storm on 2021 June 2022 in frequency band 1032 MHz by the radio telescope URAN2 are discussed in this paper. The storm was highly populated with other solar bursts such as Type III bursts and drift pairs. The occurrence rate of Sbursts was very high reaching 60 bursts per minute. All observed Sbursts were characterized by low fluxes with respect to the background radio emission. Thus special processing methods are used to retrieve spectral properties of the bursts. Some individual long Sbursts covered the whole frequency band of the URAN2 radio telescope from 10 to 32 MHz. Such extended in frequency Sbursts were recorded for the first time. 50 extended Sbursts were selected for the further analysis.Methods The Sbursts dynamic spectra with timefrequency resolutions of 100 ms and 4 kHz as well as singlefrequency profiles were used in the analysis. Due to low Sbursts intensities the drift rates were estimated from the timedifferentiated dynamic spectra highlighting the tracks of the bursts maxima. Polarization dynamic spectra were used for measuring the degree and sense of the Sbursts circular polarization. Individual Sbursts tracks were used for instant coronal inhomogeneities diagnostics. Mean Sbursts parameters retrieved from the statistical processing of the set of 50 bursts were compared with previously obtained ones.Results We concluded that by the mean durations drift rates frequency extent and the polarization all observed Sbursts could be divided into two separate groups the short and the long Sbursts. The powerlaw index of the drift ratefrequency dependence averaged over all 50 selected bursts was found to be 1.7. It was shown that sources of Sbursts most likely move through the Newkirk corona with the velocities of 0.060.08c. The powerlaw dependence of the long Sbursts durations on frequency in frequency band of 1230 MHz was obtained. Its index equal to 0.61 appeared to be very close to that for Type III bursts. From this dependence the electron velocity dispersion in the beam responsible for Sbursts generation was calculated. Its value of 0.02 indicates that the beams responsible for Sbursts generation are almost monoenergetic.Discussion It is assumed that nonmonotonic appearance of individual Sbursts tracks on the dynamic spectrum reflects density inhomogeneities encountered by the sources on their paths. From the dynamic spectra of such Sbursts the characteristic size and amplitude of these coronal inhomogeneities were detected. From the Sbursts durations and the velocities of their sources the longitudinal sizes of the latter were estimated. It was then shown that the sizes of smallscale coronal inhomogeneities were comparable to those of long Sbursts sources. Thus we concluded that individual tracks of the long Sbursts can be used for fie diagnostics the coronal plasma at heliocentric heights range from 1.7 to 3.2 Rs where Rs is the solar radius. On the other hand these tracks being ensembleaveraged give the information about the longterm large scale properties of the corona. | 2024-06-01T00:00:00Z | ['10.3389/fspas.2024.1403135', '2024FrASS..1103135D'] | null | Properties of individual Sbursts observed in the frequency band of 1032 MHz during the rising phase of 25th solar cycle | 2,024 | 0 | 0.25 | ['PUB_HTML'] | 0 | null |
2024HEAD...2110508M | The LargE Area burst Polarimeter LEAP will expose the underlying physics that governs astrophysical jets and the extreme environment surrounding newborn compact objects. LEAP will do this by making the highest fidelity polarization measurements to date of the prompt gammaray emission from a large sample of GammaRay Bursts GRBs. The LEAP science objectives are met with a single instrument a wide FOV Compton polarimeter that measures GRB polarization over the energy range from 501000 keV performs GRB spectroscopy from 20 keV to 6 MeV and selfsufficiently determines the source direction. LEAP measures polarization using seven independent polarimeter modules each with a 12 x 12 array of optically isolated highZ CsITl and lowZ plastic scintillation detectors including two plastic scintillators infused with SUP60SUPCo for calibration read out by individual PMTs. Scatter events recorded by the scintillator array within each module are used to measure polarization. The distribution of azimuthal scatter angles for these events provides a polarization signature which is further enhanced by measurement of the Compton polar scatter angle. The total effective area for polarimetry is 1000 cmSUP2SUP at energies above 100 keV. To characterize the GRB parameters spectroscopic measurements 20 keV 6 MeV are obtained using all event types both multiple and singles events with a total effective area that reaches gt3000 cmSUP2SUP between 50 and 500 keV. If approved LEAP will be deployed as an external payload on the International Space Station ISS in 2027 for a 32month mission. Over its lifetime LEAP will for the first time measure the level of polarization for a significant number of GRBs with sufficient sensitivity defined as the Minimum Detectable Polarization or MDP to determine the magnetic field structure the composition whether dominated by matter or Poynting flux and the energy dissipation mechanism of GRB jets. Specifically LEAP will measure 135 GRBs with a 50300 keV MDP of lt30 224 GRBs with an MDP of lt50 and 23 GRBs with an MDP of lt10. For brighter events LEAP will measure the energy andor time dependence of the polarization. Finally LEAP will provide burst alerts to the community following procedures developed by FermiGBM. | 2024-05-01T00:00:00Z | ['2024HEAD...2110508M'] | null | The LargE Area Burst Polarimeter LEAP A NASA Mission of Opportunity for the ISS | 2,024 | 0 | 0.3 | ['PUB_HTML'] | 0 | null |
2024HEAD...2110506S | The Compton Spectrometer and Imager COSI NASA Small Explorer mission is a Compton telescope designed to study MeV astrophysics slated for launch in 2027. COSIs main science goals include mapping the Galactic 511 keV emission and radioactive elements from nucleosynthesis studying source geometries and magnetic fields of compact objects through polarization measurements and detecting and studying gamma ray bursts. The heart of COSI consists of 16 high purity germanium doublesided strip detectors through which we can perform imaging spectroscopy and polarimetry of astrophysical sources by precisely measuring the interaction position and energy deposited during each photon interaction. To read out the germanium detectors we have developed a frontend application specific integrated circuit ASIC that preserves the energy resolution inherent to germanium while also performing precise timing measurements that allow for determining the depth of interaction in the detector. Here we present the spectral and timing performance of the frontend ASIC evaluated both on the bench and on a detector similar to the COSI flight detectors and show that the ASIC meets the specifications needed for COSI to perform its science goals. | 2024-05-01T00:00:00Z | ['2024HEAD...2110506S'] | null | Spectral and Timing Performance of COSIs Frontend ASIC | 2,024 | 0 | 0.35 | ['PUB_HTML'] | 0 | null |
2024HEAD...2130306T | The Xray astronomy satellite XRISM XRay Imaging and Spectroscopy Mission developed in collaboration between the United States and Japan was launched on September 7 2023 from the Tanegashima Space Center in Japan. Two complementary Xray telescopes Resolve and Xtend are onboard XRISM. Resolve is an ultrahigh resolution spectrometer using an Xray calorimeter while Xtend has a wide field of view using an Xray CCD camera. Both telescopes use the same type of Xray Mirror Assembly XMA which is a multinested thinfoil optics using aluminum Xray reflectors. The surface of the reflector is coated with replicated gold and the energy band is extended up to 12 keV. Ground calibration of these XMAs was performed at the Xray beamline at NASAGSFC. Their performance including the PSF the effective area and the vignetting was measured in detail before they were onboard XRISM. In this presentation the inorbit performance of the XMAs will be reported. The wide field of view of the Xtend make it possible to obtain a detailed PSF. The energydependent effective area of XtendXMA can also be obtained using the energy resolution of the Xray CCD camera. The effective area of ResolveXMA will be also measured at different energies. The PSF of ResolveXMA will be measured in the Resolves 3x3 FoV with its 35 pixels and will be compared to the PSF obtained in the ground calibration. The aim point determination of both telescopes and the accuracy of determination will also be presented. We can verify that these performances meet the mission requirements and that the launch did not affected the performance of XMAs. | 2024-05-01T00:00:00Z | ['2024HEAD...2130306T'] | null | The XRISM Xray Mirror Assemblies | 2,024 | 0 | 0.38 | ['PUB_HTML'] | 0 | null |
2016amos.confE..40Y | Parameter errors in orbital models can result in poor orbit determination OD using a traditional Kalman filter. One approach to account for these errors is to consider them in the socalled SchmidtKalman filter SKF by augmenting the state covariance matrix CM with additional parameter covariance rather than additively estimating these socalled consider parameters. This paper introduces a new SKF algorithm with polynomial chaos expansion PCESKF. The PCE approach has been proved to be more efficient than Monte Carlo method for propagating the input uncertainties onto the system response without experiencing any constraints of linear dynamics or Gaussian distributions of the uncertainty sources. The state and covariance needed in the orbit prediction step are propagated using PCE. An inclined geosynchronous orbit scenario is set up to test the proposed PCESKF based OD algorithm. The satellite orbit is propagated based on numerical integration with the uncertain coefficient of solar radiation pressure considered. The PCESKF solutions are compared with extended Kalman filter EKF SKF and PCEEKF EKF with PCE solutions. It is implied that the covariance propagation using PCE leads to more precise OD solutions in comparison with those based on linear propagation of covariance. | 2016-09-01T00:00:00Z | ['2016amos.confE..40Y'] | null | SchmidtKalman Filter with Polynomial Chaos Expansion for Orbit Determination of Space Objects | 2,016 | 0 | 0.1 | null | 0 | null |
2024GeoRL..5110635S | Ice penetrating radar sounding is the primary geophysical technique for imaging the subsurface of planetary ice shells and has the potential to directly detect the iceocean interface. However many sounding measurements may lack laterally extensive features that would aid their physical interpretation. In this scenario the detection of sparse echoes can also provide rich information on ice shell properties. To explore and demonstrate this possibility we consider three cases of isolated radar signatures porecuring eutectic melt and unattributed echoes. We show that through detection of unattributed sparse echoes the thickness of the conductive portion of Europas ice shell can be constrained. These constraints can be improved by attributing sparse echoes to thermally diagnostic signatures such as porecuring and eutectic melt. Notably this approach to radar sounding echo analysis is particularly compatible with joint inversions with other planetary geophysical observations such as tidal deformation magnetic induction and rotation state. | 2024-10-01T00:00:00Z | ['2024GeoRL..5110635S', '10.1029/2024GL110635'] | null | Constraining the Thickness of the Conductive Portion of Europas Ice Shell Using Sparse Radar Echoes | 2,024 | 0 | 0.28 | ['PUB_HTML'] | 0 | null |
2024E&PSL.63818759J | Coccolith PIC export coccolith SUP13SUPC and foraminifer CdCa are analyzed at two cores in the tropical western pacific. Enhanced coccolith PIC export correlates with low phosphate concentration in the precessional band over the past 250 kyr. Low phosphate concentration or high degree of phosphorus utilization is coupled with enhanced nitrogen fixation. The precessiondriven hydrological changes control the biogeochemical and nutrient cycling. | 2024-07-01T00:00:00Z | ['2024E&PSL.63818759J', '10.1016/j.epsl.2024.118759'] | ['Precession', 'Carbonate counter pump', 'Phosphate', 'Nitrogen fixation', 'Tropical western pacific', 'Late pleistocene'] | Precessional forcing of biogeochemical and nutrient cycling in the tropical western Pacific during the late Pleistocene | 2,024 | 0 | 0.06 | ['PUB_HTML'] | 1 | null |
2017LPI....48.1626M | Through analysis of regional drainage patterns we find evidence supporting a tectonic origin of the fretted terrain. | 2017-03-01T00:00:00Z | ['2017LPI....48.1626M'] | null | Quantitative Analysis of the Fretted Terrain Drainage Network Arabia Terra Mars | 2,017 | 0 | 0 | ['PUB_PDF'] | 0 | null |
2017LPI....48.2014B | The Stimson formation Gale Crater is interpreted to represent a dry aeolian dune system Liquid water played no role in the accumulation of this unit. | 2017-03-01T00:00:00Z | ['2017LPI....48.2014B'] | null | The Stimson Formation Determining the Morphology of a Dry Aeolian Dune System and Its Significance in Gale Crater Mars | 2,017 | 0 | 0.18 | ['PUB_PDF'] | 2 | null |
2017LPI....48.2902H | CHN compounds were identified from Murray and Murchison meteorites by high resolution mass imaging using DESIMS and their spatial distributions were revealed. | 2017-03-01T00:00:00Z | ['2017LPI....48.2902H'] | null | Organic Compound Imaging on the Surface of CM2 Carbonaceous Chondrites Using Desorption Electrospray Ionization DESI with HighResolution Mass Spectrometer | 2,017 | 0 | 0 | ['PUB_PDF'] | 0 | null |
2024PhRvC.110d5810K | We report the mass measurements of neutronrich isotopes produced via spontaneous fission of inlineformulammlmathmmlmmultiscriptsmmlmiCfmmlmimmlmn252mmlmnmmlmmultiscriptsmmlmathinlineformula using a multireflection timeofflight mass spectrograph. The mass of inlineformulammlmathmmlmmultiscriptsmmlmiCemmlmimmlmn155mmlmnmmlmmultiscriptsmmlmathinlineformula is determined experimentally for the first time. A discrepancy between the experimental and literature values was found for the mass of inlineformulammlmathmmlmmultiscriptsmmlmiSbmmlmimmlmn127mmlmnmmlmmultiscriptsmmlmathinlineformula which was previously deduced through indirect measurements. In comparison with several theoretical predictions both the values and the trend of the mass excesses of inlineformulammlmathmmlmmultiscriptsmmlmiCemmlmimmlmrowmmlmn152mmlmnmmlmtextmmlmtextmmlmn155mmlmnmmlmrowmmlmmultiscriptsmmlmathinlineformula cannot be consistently explained. The widerange and simultaneous mass measurements of the multireflection timeofflight mass spectrograph enable us to crosscheck the existing mass data and the conflict between the measured timeofflight ratio and the extracted mass would imply the necessity of reexamining them. | 2024-10-01T00:00:00Z | ['2024PhRvC.110d5810K', '10.1103/PhysRevC.110.045810'] | ['Nuclear Astrophysics'] | Comprehensive mass measurement study of inlineformulammlmathmmlmmultiscriptsmmlmiCfmmlmimmlmn252mmlmnmmlmmultiscriptsmmlmathinlineformula fission fragments with MRTOFMS and detailed study of masses of neutronrich Ce isotopes | 2,024 | 0 | 0.06 | ['PUB_HTML'] | 1 | null |
2017EGUGA..1915901G | The first orbits of Juno around Jupiter have led to a considerable improvement in the measurement of the planets even gravitational moments. We will discuss how this leads to better constraints on jovian interior models and how internal differential rotation and equations of state play an important part in the analysis. | 2017-04-01T00:00:00Z | ['2017EGUGA..1915901G'] | null | Junos first peek at Jupiters interior | 2,017 | 0 | 0.19 | ['PUB_PDF'] | 0 | null |
2017EGUGA..1915147E | The Masoala rainforest hall of the Zurich Zoo Switzerland covers a ground surface area of 10856 m2 and reaches 30 m in height. With its transparent ETFE foiled roof it provides a tropical climate for a large diversity of plants and animals. In combination with an effort to estimate dry deposition of elemental mercury we made an attempt to measure turbulent transfer velocity with an ultrasonic anemometer inside the hall. Not surprising the largest turbulence elements were on the order of the hall dimension. Although the dimensions of the hall seem to be small 200000 m3 for eddy covariance flux measurements and the air circulation inside the hall was extremely weak the spectra of wind velocity components and virtual sonic temperature obeyed the general statistical description expected under unconstrained outdoor measurement conditions. We will present results from a twoweek measurement campaign in the Masoala rainforest hall and make a suggestion for the deposition velocity to be used to estimate dry deposition of atmospheric components to the tropical vegetation surface. | 2017-04-01T00:00:00Z | ['2017EGUGA..1915147E'] | null | Turbulence Measurements in a Tropical Zoo Hall | 2,017 | 0 | 0.1 | ['PUB_PDF'] | 0 | null |
2017EGUGA..1914070H | Mercury exhibits a very dynamic magnetosphere which is partially due to strong dayside reconnection and fast magnetospheric convection. It has been shown that dayside reconnection occurs even on low magnetic shear angles across the magnetopause. This drives quasisteady region 1 fieldaligned currents FAC that are observable in insitu MESSENGER data. Here the structure of the Hermean FACsystem is discussed and compared to the terrestrial counterpart. Due to the lack of a significant ionosphere at Mercury it has to be examined how much of the poloidal FAC is reflected back to the magnetosphere closed via toroidal currents in the planetary interior or via Pedersen currents in the tenuous exosphere. This investigation gives insights into the planetary conductivity structure as well as the exospheric plasma densities. Furthermore it will be examined how much the only partially developed ring current at Mercury produces possible region 2 FAC signatures. We conclude with requirements to simulations that are needed to forecast the FAC structure on the southern hemisphere that will be closely studied with the upcoming BepiColombo mission. | 2017-04-01T00:00:00Z | ['2017EGUGA..1914070H'] | null | FieldAligned Current Systems at Mercury | 2,017 | 0 | 0.12 | ['PUB_PDF'] | 0 | null |
2017EGUGA..1914186A | In the last decade the prediction of coronal mass ejections CMEs at Earth has attracted a lot of attention from scientists all over the world. Several organizations monitor the solar activity and the solar wind embracing many of the diverse phenomena related to space weather. Despite the community wide efforts to enhance prediction models accurately forecasting a CMEs arrival time at Earth is not yet possible and the number of false alarms is still too high. With the currently limited observational possibilities of coronagraphs at L1 it may not be possible to improve the prediction error significantly. With the Solar TErrestrial RElations Observatory STEREO the research field of the interplanetary evolution of CMEs got fresh impetus and CMEs propagating outside the field of view of coronagraphs could have been studied in detail. Exploiting STEREO data several methods were developed to investigate and predict the propagation of CMEs. The logical next step in the field of CME prediction is to use and refine those methods and to envisage future space weather missions where these tools can be deployed. This talk gives an overview on existing forecasting methods and models and risks a foresight into prospective models and ideas which may enhance CME prediction. | 2017-04-01T00:00:00Z | ['2017EGUGA..1914186A'] | null | CME prediction present and future perspectives | 2,017 | 0 | 0.14 | ['PUB_PDF'] | 0 | null |
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