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| versions
list | update_date
timestamp[s] | authors_parsed
sequence |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
0706.4414 | Abdou Chbihi | F. Grenier (LAVAL Univ.), A. Chbihi (GANIL), R. Roy (LAVAL Univ.), G.
Verde (GANIL, INFN, Sezione di Catania), D. Th\'eriault (LAVAL Univ.), J.D.
Frankland (GANIL), J.P. Wieleczko (GANIL), B. Borderie (IPNO), R. Bougault
(LPCC), R. Dayras, E. Galichet (IPNO, Cnam), D. Guinet (IPNO, Ipnl), P.
Lautesse (IPNL), N. Le Neindre (IPNO), O. Lopez (LPCC), J. Moisan (GANIL), L.
Nalpas (DAPNIA), M. P\^arlog (LPCC, Nipne), M. F. Rivet (IPNO), E. Rosato, B.
Tamain (LPCC), E. Vient (LPCC), M. Vigilante (INFN, Sezione di Napoli) | Decay modes of $^{10}$C nuclei unbound state | 12 pages, 3 figures, submitted to Physics Letters B | null | null | GANIL P 07 10 | nucl-ex | null | Unbound states of $^{10}$C nuclei produced as quasi-projectiles in
$^{12}$C+$^{24}$Mg collisions at E/A = 53 and 95 MeV are studied with the Indra
detector array. Multi-particle correlation function analyses provide
experimental evidence of sequential de-excitation mechanisms through the
production of intermediate $^{9}$B, $^{6}$Be and $^{8}$Be unbound nuclei. The
relative contributions of different decay sequences to the total decay width of
the explored states is estimated semi-quantitatively. The obtained results show
that heavy-ion collisions can be used as a tool to access spectroscopic
information about exotic nuclei.
| [
{
"version": "v1",
"created": "Fri, 29 Jun 2007 13:48:55 GMT"
}
] | 2007-07-02T00:00:00 | [
[
"Grenier",
"F.",
"",
"LAVAL Univ."
],
[
"Chbihi",
"A.",
"",
"GANIL"
],
[
"Roy",
"R.",
"",
"LAVAL Univ."
],
[
"Verde",
"G.",
"",
"GANIL, INFN, Sezione di Catania"
],
[
"Thériault",
"D.",
"",
"LAVAL Univ."
],
[
"Frankland",
"J. D.",
"",
"GANIL"
],
[
"Wieleczko",
"J. P.",
"",
"GANIL"
],
[
"Borderie",
"B.",
"",
"IPNO"
],
[
"Bougault",
"R.",
"",
"LPCC"
],
[
"Dayras",
"R.",
"",
"IPNO, Cnam"
],
[
"Galichet",
"E.",
"",
"IPNO, Cnam"
],
[
"Guinet",
"D.",
"",
"IPNO, Ipnl"
],
[
"Lautesse",
"P.",
"",
"IPNL"
],
[
"Neindre",
"N. Le",
"",
"IPNO"
],
[
"Lopez",
"O.",
"",
"LPCC"
],
[
"Moisan",
"J.",
"",
"GANIL"
],
[
"Nalpas",
"L.",
"",
"DAPNIA"
],
[
"Pârlog",
"M.",
"",
"LPCC, Nipne"
],
[
"Rivet",
"M. F.",
"",
"IPNO"
],
[
"Rosato",
"E.",
"",
"LPCC"
],
[
"Tamain",
"B.",
"",
"LPCC"
],
[
"Vient",
"E.",
"",
"LPCC"
],
[
"Vigilante",
"M.",
"",
"INFN, Sezione di Napoli"
]
] |
0706.4415 | Alberto Robledo | L. G. Moyano, D. Silva, A. Robledo | Labyrinthine pathways towards supercycle attractors in unimodal maps | 8 pages, 13 figures | Central European Journal of Physics 7, 591-600 (2009) | 10.2478/s11534-009-0065-1 | null | cond-mat.stat-mech nlin.CD | null | We uncover previously unknown properties of the family of periodic
superstable cycles in unimodal maps characterized each by a Lyapunov exponent
that diverges to minus infinity. Amongst the main novel properties are the
following: i) The basins of attraction for the phases of the cycles develop
fractal boundaries of increasing complexity as the period-doubling structure
advances towards the transition to chaos. ii) The fractal boundaries, formed by
the preimages of the repellor, display hierarchical structures organized
according to exponential clusterings that manifest in the dynamics as
sensitivity to the final state and transient chaos. iii) There is a functional
composition renormalization group (RG) fixed-point map associated to the family
of supercycles. iv) This map is given in closed form by the same kind of
$q$-exponential function found for both the pitchfork and tangent bifurcation
attractors. v) There is a final stage ultra-fast dynamics towards the attractor
with a sensitivity to initial conditions that decreases as an exponential of an
exponential of time.
| [
{
"version": "v1",
"created": "Fri, 29 Jun 2007 13:50:56 GMT"
}
] | 2015-05-13T00:00:00 | [
[
"Moyano",
"L. G.",
""
],
[
"Silva",
"D.",
""
],
[
"Robledo",
"A.",
""
]
] |
0706.4416 | Brian O'Shea | Brian W. O'Shea, Michael L. Norman | Population III star formation in a Lambda CDM universe, II: Effects of a
photodissociating background | 46 pages, 14 figures (9 color). Accepted by the Astrophysical
Journal, some minor revisions | null | 10.1086/524006 | LA-UR-06-3784 | astro-ph | null | We examine aspects of primordial star formation in the presence of a
molecular hydrogen-dissociating ultraviolet background. We compare a set of AMR
hydrodynamic cosmological simulations using a single cosmological realization
but with a range of ultraviolet background strengths in the Lyman-Werner band.
This allows us to study the effects of Lyman-Werner radiation on suppressing H2
cooling at low densities as well as the high-density evolution of the
collapsing core in a self-consistent cosmological framework. We find that the
addition of a photodissociating background results in a delay of the collapse
of high density gas at the center of the most massive halo in the simulation
and, as a result, an increase in the virial mass of this halo at the onset of
baryon collapse. We find that, contrary to previous results, Population III
star formation is not suppressed for J$_{21} \geq 0.1$, but occurs even with
backgrounds as high as J$_{21} = 1$. We find that H2 cooling leads to collapse
despite the depressed core molecular hydrogen fractions due to the elevated H2
cooling rates at $T=2-5 \times 10^3$ K. We observe a relationship between the
strength of the photodissociating background and the rate of accretion onto the
evolving protostellar cloud core, with higher LW background fluxes resulting in
higher accretion rates. Finally, we find that the collapsing halo cores in our
simulations do not fragment at densities below $n \sim 10^{10}$ cm$^{-3}$
regardless of the strength of the LW background, suggesting that Population III
stars forming in halos with T$_{vir} \sim 10^4$ K may still form in isolation.
| [
{
"version": "v1",
"created": "Fri, 29 Jun 2007 13:52:42 GMT"
},
{
"version": "v2",
"created": "Fri, 28 Sep 2007 20:27:53 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"O'Shea",
"Brian W.",
""
],
[
"Norman",
"Michael L.",
""
]
] |
0706.4417 | Aaron Robertson | Aaron Robertson and Kellen Myers | Some Two Color, Four Variable Rado Numbers | 13 pages | null | null | null | math.CO | null | There exists a minimum integer $N$ such that any 2-coloring of
$\{1,2,...,N\}$ admits a monochromatic solution to $x+y+kz =\ell w$ for $k,\ell
\in \mathbb{Z}^+$, where $N$ depends on $k$ and $\ell$. We determine $N$ when
$\ell-k \in \{0,1,2,3,4,5\}$, for all $k,\ell$ for which
${1/2}((\ell-k)^2-2)(\ell-k+1)\leq k \leq \ell-4$, as well as for arbitrary $k$
when $\ell=2$.
| [
{
"version": "v1",
"created": "Fri, 29 Jun 2007 13:52:44 GMT"
}
] | 2007-07-02T00:00:00 | [
[
"Robertson",
"Aaron",
""
],
[
"Myers",
"Kellen",
""
]
] |
0706.4418 | Antony Carrington | A. Carrington, and E.A. Yelland | Fermi surface pockets in ortho-II YBa$_2$Cu$_3$O$_{6.5}$: the origin of
quantum oscillations? | null | PHYSICAL REVIEW B 76, 140508(R) (2007). | 10.1103/PhysRevB.76.140508 | null | cond-mat.supr-con cond-mat.str-el | null | In this paper we explore whether the quantum oscillation signals recently
observed in ortho-II YBa$_2$Cu$_3$O$_{6.5}$ may be explained by conventional
density functional band-structure theory. Our calculations show that the Fermi
surface of YBa$_2$Cu$_3$O$_{6.5}$ is extremely sensitive to small shifts in the
relative positions of the bands. With rigid band shifts of around 30 meV small
tubular pockets of Fermi surface develop around the Y point in the Brillouin
zone. The cross-sectional areas and band masses of the quantum oscillatory
orbits on these pockets are close to those observed. The difference between the
bandstructure of YBa$_2$Cu$_3$O$_{6.5}$ and YBa$_2$Cu$_4$O$_{8}$ are discussed.
| [
{
"version": "v1",
"created": "Fri, 29 Jun 2007 15:29:37 GMT"
},
{
"version": "v2",
"created": "Fri, 12 Oct 2007 15:35:12 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Carrington",
"A.",
""
],
[
"Yelland",
"E. A.",
""
]
] |
0706.4419 | Ray Protheroe | Gregory Benford, R.J. Protheroe | Fossil AGN jets as ultra high energy particle accelerators | 11 pages, 6 figures, additional references and explanations. Accepted
for publication in MNRAS | null | 10.1111/j.1365-2966.2007.12565.x | null | astro-ph | null | Remnants of AGN jets and their surrounding cocoons leave colossal
magnetohydrodynamic (MHD) fossil structures storing total energies ~10^{60}
erg. The original active galacic nucleus (AGN) may be dead but the fossil will
retain its stable configuration resembling the reversed-field pinch (RFP)
encountered in laboratory MHD experiments.
In an RFP the longitudinal magnetic field changes direction at a critical
distance from the axis, leading to magnetic re-connection there, and to slow
decay of the large-scale RFP field. We show that this field decay induces
large-scale electric fields which can accelerate cosmic rays with an E^{-2}
power-law up to ultra-high energies with a cut-off depending on the fossil
parameters. The cut-off is expected to be rigidity dependent, implying the
observed composition would change from light to heavy close to the cut-off if
one or two nearby AGN fossils dominate. Given that several percent of the
universe's volume may house such slowly decaying structures, these fossils may
even re-energize ultra-high energy cosmic rays from distant/old sources,
offsetting the ``GZK-losses'' due to interactions with photons of the cosmic
microwave background radiation and giving evidence of otherwise undetectable
fossils. In this case the composition would remain light to the highest
energies if distant sources or fossils dominated, but otherwise would be mixed.
It is hoped the new generation of cosmic ray experiments such as the Pierre
Auger Observatory and ultra-high energy neutrino telescopes such as ANITA and
lunar Cherenkov experiments will clarify this.
| [
{
"version": "v1",
"created": "Fri, 29 Jun 2007 13:55:17 GMT"
},
{
"version": "v2",
"created": "Sun, 14 Oct 2007 00:33:35 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Benford",
"Gregory",
""
],
[
"Protheroe",
"R. J.",
""
]
] |
0706.4420 | Aaron Robertson | Tom Brown, Bruce M. Landman, and Aaron Robertson | Bounds on Van der Waerden Numbers and Some Related Functions | 13 pages | null | null | null | math.CO | null | For positive integers $s$ and $k_1, k_2, ..., k_s$, let $w(k_1,k_2,...,k_s)$
be the minimum integer $n$ such that any $s$-coloring $\{1,2,...,n\} \to
\{1,2,...,s\}$ admits a $k_i$-term arithmetic progression of color $i$ for some
$i$, $1 \leq i \leq s$. In the case when $k_1=k_2=...=k_s=k$ we simply write
$w(k;s)$.
That such a minimum integer exists follows from van der Waerden's theorem on
arithmetic progressions.
In the present paper we give a lower bound for $w(k,m)$ for each fixed $m$.
We include a table with values of $w(k,3)$ which match this lower bound closely
for $5 \leq k \leq 16$. We also give an upper bound for $w(k,4)$, an upper
bound for $w(4;s)$, and a lower bound for $w(k;s)$ for an arbitrary fixed $k$.
We discuss a number of other functions that are closely related to the van der
Waerden function.
| [
{
"version": "v1",
"created": "Fri, 29 Jun 2007 13:56:47 GMT"
}
] | 2007-07-02T00:00:00 | [
[
"Brown",
"Tom",
""
],
[
"Landman",
"Bruce M.",
""
],
[
"Robertson",
"Aaron",
""
]
] |
0706.4421 | Stephen Tawn | Stephen Tawn | A presentation for Hilden's subgroup of the braid group | minor changes, 17 pages | Math. Res. Lett., 15(6), 2008, 1277-1293 | null | null | math.GR | null | Consider the unit ball, B = D x [0,1], containing n unknotted arcs a_1, ...
a_n such that the boundary of each a_i lies in D x {0}. We give a finite
presentation for the mapping class group of B fixing the arcs {a_1, ..., a_n}
setwise and fixing D x {1} pointwise. This presentation is calculated using the
action of this group on a simply-connected complex.
| [
{
"version": "v1",
"created": "Fri, 29 Jun 2007 14:14:53 GMT"
},
{
"version": "v2",
"created": "Mon, 8 Oct 2007 12:17:00 GMT"
}
] | 2009-02-27T00:00:00 | [
[
"Tawn",
"Stephen",
""
]
] |
0706.4422 | Alberto Robledo | A. Robledo, L. G. Moyano | Dynamics towards the Feigenbaum attractor | 8 pages, 12 figures | Brazilian Journal of Physics 39, 364-370 (2009) | 10.1103/PhysRevE.77.036213 | null | cond-mat.stat-mech nlin.CD | null | We expose at a previously unknown level of detail the features of the
dynamics of trajectories that either evolve towards the Feigenbaum attractor or
are captured by its matching repellor. Amongst these features are the
following: i) The set of preimages of the attractor and of the repellor are
embedded (dense) into each other. ii) The preimage layout is obtained as the
limiting form of the rank structure of the fractal boundaries between attractor
and repellor positions for the family of supercycle attractors. iii) The joint
set of preimages for each case form an infinite number of families of
well-defined phase-space gaps in the attractor or in the repellor. iv) The gaps
in each of these families can be ordered with decreasing width in accord to
power laws and are seen to appear sequentially in the dynamics generated by
uniform distributions of initial conditions. v) The power law with log-periodic
modulation associated to the rate of approach of trajectories towards the
attractor (and to the repellor) is explained in terms of the progression of gap
formation. vi) The relationship between the law of rate of convergence to the
attractor and the inexhaustible hierarchy feature of the preimage structure is
elucidated.
| [
{
"version": "v1",
"created": "Fri, 29 Jun 2007 14:00:43 GMT"
}
] | 2013-05-29T00:00:00 | [
[
"Robledo",
"A.",
""
],
[
"Moyano",
"L. G.",
""
]
] |
0706.4423 | Yi-Fei Wang | Yi-Fei Wang, Chang-De Gong, and Z. D. Wang | Tuning Kinetic Magnetism of Strongly Correlated Electrons via Staggered
Flux | 4 pages, 5 figures, 1 table | Phys. Rev. Lett. 100, 037202 (2008) | 10.1103/PhysRevLett.100.037202 | null | cond-mat.str-el cond-mat.stat-mech | null | We explore the kinetic magnetism of the infinite-$U$ repulsive Hubbard models
at low hole densities on various lattices with nearest-neighbor hopping
integrals modulated by a staggered magnetic flux $\pm\phi$. Tuning $\phi$ from
0 to $\pi$ makes the ground state (GS) change from a Nagaoka-type ferromagnetic
state to a Haerter-Shastry-type antiferromagnetic state at a critical $\phi_c$,
with both states being of kinetic origin. Intra-plaquette spin correlation, as
well as the GS energy, signals such a quantum criticality. This tunable kinetic
magnetism is generic, and appears in chains, ladders and two-dimensional
lattices with squares or triangles as elementary constituents.
| [
{
"version": "v1",
"created": "Fri, 29 Jun 2007 14:10:22 GMT"
}
] | 2008-02-05T00:00:00 | [
[
"Wang",
"Yi-Fei",
""
],
[
"Gong",
"Chang-De",
""
],
[
"Wang",
"Z. D.",
""
]
] |
0706.4424 | Raffaele D'Abrusco | R. D'Abrusco, A. Staiano, G. Longo, M. Paolillo, E. De Filippis | Steps toward a classifier for the Virtual Observatory. I. Classifying
the SDSS photometric archive | To appear in the Proceedings of the "1st Workshop of Astronomy and
Astrophysics for Students" - Naples, 19-20 April 2006 | null | null | null | astro-ph | null | Modern photometric multiband digital surveys produce large amounts of data
that, in order to be effectively exploited, need automatic tools capable to
extract from photometric data an objective classification. We present here a
new method for classifying objects in large multi-parametric photometric data
bases, consisting of a combination of a clustering algorithm and a cluster
agglomeration tool. The generalization capabilities and the potentialities of
this approach are tested against the complexity of the Sloan Digital Sky Survey
archive, for which an example of application is reported.
| [
{
"version": "v1",
"created": "Fri, 29 Jun 2007 14:10:33 GMT"
}
] | 2007-07-02T00:00:00 | [
[
"D'Abrusco",
"R.",
""
],
[
"Staiano",
"A.",
""
],
[
"Longo",
"G.",
""
],
[
"Paolillo",
"M.",
""
],
[
"De Filippis",
"E.",
""
]
] |
0706.4425 | Boris Shklovskii | B. I. Shklovskii | A simple model of Coulomb disorder and screening in graphene | 2.5 pages, twice longer than previous version | null | 10.1103/PhysRevB.76.233411 | null | cond-mat.mes-hall cond-mat.dis-nn | null | We suggest a simple model of disorder in graphene assuming that there are
randomly distributed positive and negative centers with equal concentration
$N/2$ in the bulk of silicon oxide substrate. We show that at zero gate voltage
such disorder creates two-dimensional concentration $n_0 \sim N^{2/3}$ of
electrons and holes in graphene. Electrons and holes reside in alternating in
space puddles of the size $R_0 \sim N^{-1/3}$. A typical puddle has only one or
two carriers in agreement with recent scanning single electron transistor
experiment.
| [
{
"version": "v1",
"created": "Fri, 29 Jun 2007 14:10:46 GMT"
},
{
"version": "v2",
"created": "Wed, 19 Sep 2007 15:36:26 GMT"
},
{
"version": "v3",
"created": "Mon, 29 Oct 2007 15:46:50 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Shklovskii",
"B. I.",
""
]
] |
0706.4426 | Christophe Martayan | Christophe Martayan (GEPI), Michele Floquet (GEPI), Anne-Marie Hubert
(GEPI), Juan Guti\'errez-Soto (GEPI), Juan Fabregat, Coralie Neiner (GEPI),
Malek Mekkas (GEPI) | Be stars and binaries in the field of the SMC open cluster NGC330 with
VLT-FLAMES | english not yet corrected, 23 pages, 4th article about the study in
the LMC NGC2004 and SMC NGC330 | Astron.Astrophys.472:577-586,2007 | 10.1051/0004-6361:20077390 | null | astro-ph | null | Observations of hot stars belonging to the young cluster SMC-NGC330 and its
surrounding region were obtained with the VLT-GIRAFFE facilities in MEDUSA
mode. We investigated the B and Be star properties and proportions in this
environment of low metallicity. We also searched for rapid variability in Be
stars using photometric databases. With spectroscopic measurements we
characterized the emission and properties of Be stars. By cross-correlation
with photometric databases such as MACHO and OGLE, we searched for binaries in
our sample of hot stars, as well as for short-term variability in Be stars. We
report on the global characteristics of the Be star sample (131 objects). We
find that the proportion of early Be stars with a large equivalent width of the
Halpha emission line is higher in the SMC than in the LMC and MW. We find a
slight increase in the proportion of Be stars compared to B-type stars with
decreasing metallicity. We also discovered spectroscopic and photometric
binaries, and for the latter we give their orbital period. We identify 13 Be
stars with short-term variability. We determine their period(s) and find that 9
Be stars are multiperiodic.
| [
{
"version": "v1",
"created": "Fri, 29 Jun 2007 14:13:02 GMT"
}
] | 2014-11-18T00:00:00 | [
[
"Martayan",
"Christophe",
"",
"GEPI"
],
[
"Floquet",
"Michele",
"",
"GEPI"
],
[
"Hubert",
"Anne-Marie",
"",
"GEPI"
],
[
"Gutiérrez-Soto",
"Juan",
"",
"GEPI"
],
[
"Fabregat",
"Juan",
"",
"GEPI"
],
[
"Neiner",
"Coralie",
"",
"GEPI"
],
[
"Mekkas",
"Malek",
"",
"GEPI"
]
] |
0706.4427 | Christof Wetterich | C.Wetterich | Growing neutrinos and cosmological selection | new material on time varying constants, new figures, 8 pages, 4
figures | Phys.Lett.B655:201-208,2007 | 10.1016/j.physletb.2007.08.060 | null | hep-ph | null | The time evolution of a cosmological scalar field can be stopped by an
increasing mass of the neutrinos. This leads to a transition from a
cosmological scaling solution with dynamical dark energy at early time to a
cosmological constant dominated universe at late time. The trigger for the
transition is set at the time when the neutrinos become non-relativistic. The
characteristic mass scale for dark energy is thus related to the neutrino mass,
the only known particle physics scale in its vicinity. This explains the ``why
now problem'' for dark energy. We present a particle physics realization of
this ``growing matter'' scenario. It is based on the very slowly varying mass
of a superheavy scalar triplet field whose expectation value dominates the
light neutrino masses.
| [
{
"version": "v1",
"created": "Fri, 29 Jun 2007 14:14:02 GMT"
},
{
"version": "v2",
"created": "Wed, 1 Aug 2007 11:37:41 GMT"
}
] | 2008-11-26T00:00:00 | [
[
"Wetterich",
"C.",
""
]
] |
0706.4428 | Massimo Giovannini | Massimo Giovannini | Semi-analytical approach to magnetized temperature autocorrelations | 40 pages, 13 figures | PMCPhys.A1:5,2007 | 10.1186/1754-0410-1-5 | CERN-PH-TH/2007-110 | astro-ph gr-qc hep-ph hep-th | null | The cosmic microwave background (CMB) temperature autocorrelations, induced
by a magnetized adiabatic mode of curvature inhomogeneities, are computed with
semi-analytical methods. As suggested by the latest CMB data, a nearly
scale-invariant spectrum for the adiabatic mode is consistently assumed. In
this situation, the effects of a fully inhomogeneous magnetic field are
scrutinized and constrained with particular attention to harmonics which are
relevant for the region of Doppler oscillations. Depending on the parameters of
the stochastic magnetic field a hump may replace the second peak of the angular
power spectrum. Detectable effects on the Doppler region are then expected only
if the magnetic power spectra have quasi-flat slopes and typical amplitude
(smoothed over a comoving scale of Mpc size and redshifted to the epoch of
gravitational collapse of the protogalaxy) exceeding 0.1 nG. If the magnetic
energy spectra are bluer (i.e. steeper in frequency) the allowed value of the
smoothed amplitude becomes, comparatively, larger (in the range of 20 nG). The
implications of this investigation for the origin of large-scale magnetic
fields in the Universe are discussed. Connections with forthcoming experimental
observations of CMB temperature fluctuations are also suggested and partially
explored.
| [
{
"version": "v1",
"created": "Fri, 29 Jun 2007 14:22:02 GMT"
}
] | 2008-11-26T00:00:00 | [
[
"Giovannini",
"Massimo",
""
]
] |
0706.4429 | Maria Rozanska | A. Matyja, M. Rozanska, et al (for the Belle Collaboration) | Observation of B^0 \to D^{*-} \tau^+ \nu_{\tau} decay at Belle | 6 pages, 3 figures, submitted to Phys. Rev. Lett | Phys.Rev.Lett.99:191807,2007 | 10.1103/PhysRevLett.99.191807 | null | hep-ex | null | We report an observation of the decay $B^0\to D^{*-} \tau^+ \nu_{\tau}$ in a
data sample containing $535\times10^6$ $B\bar{B}$ pairs collected with the
Belle detector at the KEKB asymmetric-energy $e^+e^-$ collider. We find a
signal with a significance of 5.2 standard deviations and measure the branching
fraction $\mathcal{B}(B^0\to D^{*-} \tau ^+ \nu_{\tau})=(2.02 ^{+0.40}_{-0.37}
(stat) \pm 0.37 (syst)) % $. This is the first observation of an exclusive $B$
decay with a $b \to c \tau \nu_{\tau}$ transition.
| [
{
"version": "v1",
"created": "Fri, 29 Jun 2007 14:27:28 GMT"
},
{
"version": "v2",
"created": "Sat, 8 Sep 2007 17:07:50 GMT"
}
] | 2019-08-13T00:00:00 | [
[
"Matyja",
"A.",
""
],
[
"Rozanska",
"M.",
""
]
] |
0706.4430 | Andre Utermann | Daniel Boer, Andre Utermann, Erik Wessels | Investigating the extended geometric scaling region at LHC with
polarized and unpolarized final states | 2 pages, 2 figures. Contributed to Workshop on Heavy Ion Collisions
at the LHC: Last Call for Predictions, Geneva, Switzerland, 14 May - 8 Jun
2007 | null | null | null | hep-ph | null | We present predictions for charged hadron production and Lambda polarization
in p-p and p-Pb collisions at the LHC using the saturation inspired DHJ model
for the dipole cross section in the extended geometric scaling region.
| [
{
"version": "v1",
"created": "Fri, 29 Jun 2007 14:30:47 GMT"
}
] | 2007-07-02T00:00:00 | [
[
"Boer",
"Daniel",
""
],
[
"Utermann",
"Andre",
""
],
[
"Wessels",
"Erik",
""
]
] |
0706.4431 | Luca Parisi | Luca Parisi, Marco Bruni, Roy Maartens, Kevin Vandersloot | The Einstein static universe in Loop Quantum Cosmology | 12 pages, 7 figures; v2: minor changes to match published version in
Classical and Quantum Gravity | Class.Quant.Grav.24:6243-6254,2007 | 10.1088/0264-9381/24/24/007 | null | gr-qc astro-ph hep-th | null | Loop Quantum Cosmology strongly modifies the high-energy dynamics of
Friedman-Robertson-Walker models and removes the big-bang singularity. We
investigate how LQC corrections affect the stability properties of the Einstein
static universe. In General Relativity, the Einstein static model with positive
cosmological constant Lambda is unstable to homogeneous perturbations. We show
that LQC modifications can lead to a centre of stability for a large enough
positive value of Lambda.
| [
{
"version": "v1",
"created": "Fri, 29 Jun 2007 14:32:47 GMT"
},
{
"version": "v2",
"created": "Thu, 17 Jan 2008 14:00:23 GMT"
}
] | 2008-11-26T00:00:00 | [
[
"Parisi",
"Luca",
""
],
[
"Bruni",
"Marco",
""
],
[
"Maartens",
"Roy",
""
],
[
"Vandersloot",
"Kevin",
""
]
] |
0706.4432 | Willemien Kets | Willemien Kets | The minority game: An economics perspective | 30 pages, 4 figures | null | null | null | q-fin.GN physics.soc-ph | null | This paper gives a critical account of the minority game literature. The
minority game is a simple congestion game: players need to choose between two
options, and those who have selected the option chosen by the minority win. The
learning model proposed in this literature seems to differ markedly from the
learning models commonly used in economics. We relate the learning model from
the minority game literature to standard game-theoretic learning models, and
show that in fact it shares many features with these models. However, the
predictions of the learning model differ considerably from the predictions of
most other learning models. We discuss the main predictions of the learning
model proposed in the minority game literature, and compare these to
experimental findings on congestion games.
| [
{
"version": "v1",
"created": "Fri, 29 Jun 2007 14:55:44 GMT"
}
] | 2008-12-02T00:00:00 | [
[
"Kets",
"Willemien",
""
]
] |
0706.4433 | Klaus Hornberger | Bassano Vacchini, Klaus Hornberger | Relaxation dynamics of a quantum Brownian particle in an ideal gas | 15 pages; to appear in Eur. Phys. J. Special Topics (2007) | Eur. Phys. J. Special Topics 151, 59-72 (2007) | 10.1140/epjst/e2007-00362-9 | null | quant-ph | null | We show how the quantum analog of the Fokker-Planck equation for describing
Brownian motion can be obtained as the diffusive limit of the quantum linear
Boltzmann equation. The latter describes the quantum dynamics of a tracer
particle in a dilute, ideal gas by means of a translation-covariant master
equation. We discuss the type of approximations required to obtain the
generalized form of the Caldeira-Leggett master equation, along with their
physical justification. Microscopic expressions for the diffusion and
relaxation coefficients are obtained by analyzing the limiting form of the
equation in both the Schroedinger and the Heisenberg picture.
| [
{
"version": "v1",
"created": "Fri, 29 Jun 2007 14:58:47 GMT"
}
] | 2007-12-20T00:00:00 | [
[
"Vacchini",
"Bassano",
""
],
[
"Hornberger",
"Klaus",
""
]
] |
0706.4434 | Matteo Rizzi | M. Rizzi, A. Imambekov | Pairing of 1D Bose-Fermi mixtures with unequal masses | 7 pages, 5 figures | Phys. Rev. A 77, 023621 (2008) | 10.1103/PhysRevA.77.023621 | null | cond-mat.str-el cond-mat.other | null | We have considered one-dimensional Bose-Fermi mixture with equal densities
and unequal masses using numerical density matrix renormalization group (DMRG).
For the mass ratio of K-Rb mixture and attraction between bosons and fermions,
we determined the phase diagram. For weak boson-boson interactions, there is a
direct transition between two-component Luttinger liquid and collapsed phases
as the boson-fermion attraction is increased. For strong enough boson-boson
interactions, we find an intermediate "paired" phase, which is a
single-component Luttinger liquid of composite particles. We investigated
correlation functions of such a "paired" phase, studied the stability of
"paired" phase to density imbalance, and discussed various experimental
techniques which can be used to detect it.
| [
{
"version": "v1",
"created": "Fri, 29 Jun 2007 15:04:08 GMT"
},
{
"version": "v2",
"created": "Wed, 12 Mar 2008 09:52:21 GMT"
}
] | 2009-08-20T00:00:00 | [
[
"Rizzi",
"M.",
""
],
[
"Imambekov",
"A.",
""
]
] |
0706.4435 | Daniel Mazin | MAGIC Collaboration: J. Albert, et al | Discovery of Very High Energy gamma-rays from 1ES 1011+496 at z=0.212 | 4 pages, 6 figures, minor changes to fit the ApJ version | Astrophys.J.667:L21-L23,2007 | 10.1086/521982 | MPP-2007-88 | astro-ph | null | We report on the discovery of Very High Energy (VHE) gamma-ray emission from
the BL Lacertae object 1ES1011+496. The observation was triggered by an optical
outburst in March 2007 and the source was observed with the MAGIC telescope
from March to May 2007. Observing for 18.7 hr we find an excess of 6.2 sigma
with an integrated flux above 200 GeV of (1.58$\pm0.32) 10^{-11}$ photons
cm$^{-2}$ s$^{-1}$. The VHE gamma-ray flux is >40% higher than in March-April
2006 (reported elsewhere), indicating that the VHE emission state may be
related to the optical emission state. We have also determined the redshift of
1ES1011+496 based on an optical spectrum that reveals the absorption lines of
the host galaxy. The redshift of z=0.212 makes 1ES1011+496 the most distant
source observed to emit VHE gamma-rays up to date.
| [
{
"version": "v1",
"created": "Fri, 29 Jun 2007 16:48:03 GMT"
},
{
"version": "v2",
"created": "Tue, 4 Dec 2007 18:55:41 GMT"
}
] | 2008-11-26T00:00:00 | [
[
"MAGIC Collaboration",
"",
""
],
[
"Albert",
"J.",
""
]
] |
0706.4436 | Jukka Kiukas | J. Kiukas, P. Lahti | On the moment limit of quantum observables, with an application to the
balanced homodyne detection | 22 pages, no figures | null | 10.1080/09500340701624658 | null | quant-ph | null | We consider the moment operators of the observable (i.e. a semispectral
measure or POM) associated with the balanced homodyne detection statistics,
with paying attention to the correct domains of these unbounded operators. We
show that the high amplitude limit, when performed on the moment operators,
actually determines uniquely the entire statistics of a rotated quadrature
amplitude of the signal field, thereby verifying the usual assumption that the
homodyne detection achieves a measurement of that observable. We also consider,
in a general setting, the possibility of constructing a measurement of a single
quantum observable from a sequence of observables by taking the limit on the
level of moment operators of these observables. In this context, we show that
under some natural conditions (each of which is satisfied by the homodyne
detector example), the existence of the moment limits ensures that the
underlying probability measures converge weakly to the probability measure of
the limiting observable. The moment approach naturally requires that the
observables be determined by their moment operator sequences (which does not
automatically happen), and it turns out, in particular, that this is the case
for the balanced homodyne detector.
| [
{
"version": "v1",
"created": "Fri, 29 Jun 2007 15:05:38 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Kiukas",
"J.",
""
],
[
"Lahti",
"P.",
""
]
] |
0706.4437 | Thomas Cokelaer | Thomas Cokelaer | Gravitational waves from inspiralling compact binaries: hexagonal
template placement and its efficiency in detecting physical signals | 15 pages, 43 figures | Phys.Rev.D76:102004,2007 | 10.1103/PhysRevD.76.102004 | null | gr-qc | null | Matched filtering is used to search for gravitational waves emitted by
inspiralling compact binaries in data from the ground-based interferometers.
One of the key aspects of the detection process is the design of a template
bank that covers the astrophysically pertinent parameter space. In an earlier
paper, we described a template bank that is based on a square lattice. Although
robust, we showed that the square placement is over-efficient, with the
implication that it is computationally more demanding than required. In this
paper, we present a template bank based on an hexagonal lattice, which size is
reduced by 40% with respect to the proposed square placement. We describe the
practical aspects of the hexagonal template bank implementation, its size, and
computational cost. We have also performed exhaustive simulations to
characterize its efficiency and safeness. We show that the bank is adequate to
search for a wide variety of binary systems (primordial black holes, neutron
stars and stellar mass black holes) and in data from both current detectors
(initial LIGO, Virgo and GEO600) as well as future detectors (advanced LIGO and
EGO). Remarkably, although our template bank placement uses a metric arising
from a particular template family, namely stationary phase approximation, we
show that it can be used successfully with other template families (e.g., Pade
resummation and effective one-body approximation). This quality of being
effective for different template families makes the proposed bank suitable for
a search that would use several of them in parallel (e.g., in a binary black
hole search). The hexagonal template bank described in this paper is currently
used to search for non-spinning inspiralling compact binaries in data from the
Laser Interferometer Gravitational-Wave Observatory (LIGO).
| [
{
"version": "v1",
"created": "Fri, 29 Jun 2007 18:46:50 GMT"
}
] | 2008-11-26T00:00:00 | [
[
"Cokelaer",
"Thomas",
""
]
] |
0706.4438 | J. Piilo | J. Piilo, S. Maniscalco, K. Harkonen, and K.-A. Suominen | Non-Markovian quantum jumps | 4 pages, 2 figures.V2: rewritten abstract and introduction, title
modified. V3: published version, new example case with photonic band gap | Phys. Rev. Lett. 100, 180402 (2008) | 10.1103/PhysRevLett.100.180402 | null | quant-ph | null | Open quantum systems that interact with structured reservoirs exhibit
non-Markovian dynamics. We present a quantum jump method for treating the
dynamics of such systems. This approach is a generalization of the standard
Monte Carlo Wave Function (MCWF) method for Markovian dynamics. The MCWF method
identifies decay rates with jump probabilities and fails for non-Markovian
systems where the time-dependent rates become temporarily negative. Our
non-Markovian quantum jump (NMQJ) approach circumvents this problem and
provides an efficient unravelling of the ensemble dynamics.
| [
{
"version": "v1",
"created": "Fri, 29 Jun 2007 15:10:43 GMT"
},
{
"version": "v2",
"created": "Fri, 2 Nov 2007 12:09:01 GMT"
},
{
"version": "v3",
"created": "Tue, 6 May 2008 06:56:57 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Piilo",
"J.",
""
],
[
"Maniscalco",
"S.",
""
],
[
"Harkonen",
"K.",
""
],
[
"Suominen",
"K. -A.",
""
]
] |
0706.4439 | Robert Wagner | Robert Wagner (for the MAGIC Collaboration) | AGN Observations in the GeV/TeV Energy Range with the MAGIC Telescope | 7 pages, 8 figures, to appear in the proceedings of Extragalactic
Jets: Theory and Observation from Radio to Gamma Ray, Girdwood (AK), May 2007 | ASP Conf. Ser. 386 (2008) 295 | null | MPP-2007-83 | astro-ph | null | MAGIC currently is the largest imaging atmospheric Cerenkov telescope
world-wide. Since 2004, gamma-ray emission from several active galactic nuclei
in the GeV/TeV energy range has been detected, some of which were newly
discovered as very-high energy gamma-ray sources. The gamma-rays are assumed to
originate from particle acceleration processes in the AGN jets. We give an
overview of the AGN observed and detected by MAGIC, discuss spectral and
temporal properties of these and show physics implications of some selected
observations.
| [
{
"version": "v1",
"created": "Fri, 29 Jun 2007 16:48:10 GMT"
}
] | 2008-06-11T00:00:00 | [
[
"Wagner",
"Robert",
"",
"for the MAGIC Collaboration"
]
] |
0706.4440 | Craig Alan Feinstein | Craig Alan Feinstein | 2-State 3-Symbol Universal Turing Machines Do Not Exist | 1 page | null | null | null | cs.OH | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In this brief note, we give a simple information-theoretic proof that 2-state
3-symbol universal Turing machines cannot possibly exist, unless one loosens
the definition of "universal".
| [
{
"version": "v1",
"created": "Fri, 29 Jun 2007 16:47:40 GMT"
},
{
"version": "v2",
"created": "Thu, 5 Jul 2007 15:16:11 GMT"
},
{
"version": "v3",
"created": "Mon, 27 Aug 2007 19:17:08 GMT"
},
{
"version": "v4",
"created": "Thu, 30 Aug 2007 19:55:30 GMT"
},
{
"version": "v5",
"created": "Fri, 9 Dec 2011 18:34:17 GMT"
}
] | 2011-12-12T00:00:00 | [
[
"Feinstein",
"Craig Alan",
""
]
] |
0706.4441 | Stuart Armstrong XV | Stuart Armstrong | Free $n$-distributions: holonomy, sub-Riemannian structures, Fefferman
constructions and dual distributions | First Draft | null | null | null | math.DG math.AP math.MG | null | This paper analyses the parabolic geometries generated by a free
$n$-distribution in the tangent space of a manifold. It shows that certain
holonomy reductions of the associated normal Tractor connections, imply
preferred connections with special properties, along with Riemannian or
sub-Riemannian structures on the manifold. It constructs examples of these
holonomy reductions in the simplest cases. The main results, however, lie in
the free 3-distributions. In these cases, there are normal Fefferman
constructions over CR and Lagrangian contact structures corresponding to
holonomy reductions to SO(4,2) and SO(3,3), respectively. There is also a
fascinating construction of a `dual' distribution when the holonomy reduces to
$G_2'$.
| [
{
"version": "v1",
"created": "Fri, 29 Jun 2007 15:18:57 GMT"
}
] | 2007-07-02T00:00:00 | [
[
"Armstrong",
"Stuart",
""
]
] |
0706.4442 | Robert Wagner | Robert Wagner | A First Synoptic Blazar Study Comprising Thirteen Blazars Visible in
E>100 GeV Gamma-Rays | 4 pages, 4 figures, to appear in the proceedings of the 30th
International Cosmic Ray Conference, Merida, July 2007 | Proc. 30th Int. Cosm. Ray Conf., R. Caballero et al. (eds.), UNAM,
Mexico City, 2008, Vol. 3, pg. 881-884 | null | MPP-2007-85 | astro-ph | null | Since 2002, the number of detected blazars at E_\gamma > 100 GeV has more
than doubled. I study all currently known BL Lac-type objects with published
energy spectra. Their intrinsic energy spectra are reconstructed by removing
extragalactic background light attenuation effects. The emission properties are
then compared and correlated among each other, with X-ray data, and with the
individual black hole masses. In addition, I consider temporal properties of
the very high energy gamma-ray flux. Key findings concern the flux--black hole
mass and variability scale--black hole mass connections and the correlation of
the spectral slope and the luminosity. As a specific application, the study
allows to constrain the still undetermined redshift of the blazar PG 1553+113.
| [
{
"version": "v1",
"created": "Fri, 29 Jun 2007 15:32:56 GMT"
}
] | 2009-01-08T00:00:00 | [
[
"Wagner",
"Robert",
""
]
] |
0706.4443 | Hendrik van Hees | H. van Hees and R. Rapp | Thermal Dileptons at LHC | 2 pages, 2 figures, contributed to Workshop on Heavy Ion Collisions
at the LHC: Last Call for Predictions, Geneva, Switzerland, 14 May - 8 Jun
2007 v2: acknowledgment included | Journal of Physics G 35, 1 (2008), p 153 | 10.1088/0954-3899/35/5/054001 | null | hep-ph nucl-ex nucl-th | null | We predict dilepton invariant-mass spectra for central 5.5 ATeV Pb-Pb
collisions at LHC. Hadronic emission in the low-mass region is calculated using
in-medium spectral functions of light vector mesons within hadronic many-body
theory. In the intermediate-mass region thermal radiation from the Quark-Gluon
Plasma, evaluated perturbatively with hard-thermal loop corrections, takes
over. An important source over the entire mass range are decays of correlated
open-charm hadrons, rendering the nuclear modification of charm and bottom
spectra a critical ingredient.
| [
{
"version": "v1",
"created": "Fri, 29 Jun 2007 15:35:36 GMT"
},
{
"version": "v2",
"created": "Sat, 30 Jun 2007 22:23:44 GMT"
}
] | 2008-04-22T00:00:00 | [
[
"van Hees",
"H.",
""
],
[
"Rapp",
"R.",
""
]
] |
0706.4444 | Manolis K. Georgoulis | M. K. Georgoulis, N.-E. Raouafi, C. J Henney | Automatic Active-Region Identification and Azimuth Disambiguation of the
SOLIS/VSM Full-Disk Vector Magnetograms | 8 pages, 4 Figures, Proceedings of the NSO Workshop 24, ASP Conf.
Series, submitted | null | null | null | astro-ph | null | The Vector Spectromagnetograph (VSM) of the NSO's Synoptic Optical Long-Term
Investigations of the Sun (SOLIS) facility is now operational and obtains the
first-ever vector magnetic field measurements of the entire visible solar
hemisphere. To fully exploit the unprecedented SOLIS/VSM data, however, one
must first address two critical problems: first, the study of solar active
regions requires an automatic, physically intuitive, technique for
active-region identification in the solar disk. Second, use of active-region
vector magnetograms requires removal of the azimuthal $180^o$-ambiguity in the
orientation of the transverse magnetic field component. Here we report on an
effort to address both problems simultaneously and efficiently. To identify
solar active regions we apply an algorithm designed to locate complex,
flux-balanced, magnetic structures with a dominant E-W orientation on the disk.
Each of the disk portions corresponding to active regions is thereafter
extracted and subjected to the Nonpotential Magnetic Field Calculation (NPFC)
method that provides a physically-intuitive solution of the 180-degree
ambiguity. Both algorithms have been integrated into the VSM data pipeline and
operate in real time, without human intervention. We conclude that this
combined approach can contribute meaningfully to our emerging capability for
full-disk vector magnetography as pioneered by SOLIS today and will be carried
out by ground-based and space-borne magnetographs in the future.
| [
{
"version": "v1",
"created": "Fri, 29 Jun 2007 15:33:27 GMT"
}
] | 2007-07-02T00:00:00 | [
[
"Georgoulis",
"M. K.",
""
],
[
"Raouafi",
"N. -E.",
""
],
[
"Henney",
"C. J",
""
]
] |
0706.4445 | Christiano de Matos | Christiano J. S. de Matos (1), Leonardo de S. Menezes (2), Ant\^onio
M. Brito-Silva (3), M. A. Martinez G\'amez (4), Anderson S. L. Gomes (2), and
Cid B. de Ara\'ujo (2) ((1) Programa de P\'os-Grad. Eng. El\'etrica,
Universidade Presbiteriana Mackenzie, S\~ao Paulo, Brazil, (2) Departamento
de F\'isica, Universidade Federal de Pernambuco, Recife, Brazil, (3) Programa
de P\'os-Grad. em Ci\^encia de Materiais, Universidade Federal de Pernambuco,
Recife, Brazil, (4) Centro de Investigaciones en Optica, Leon, Mexico) | Random Fiber Laser | 15 pages, 3 figures | null | 10.1103/PhysRevLett.99.153903 | null | physics.optics | null | We investigate the effects of two dimensional confinement on the lasing
properties of a classical random laser system operating in the incoherent
feedback (diffusive) regime. A suspension of 250nm rutile (TiO2) particles in a
Rhodamine 6G solution was inserted into the hollow core of a photonic crystal
fiber (PCF) generating the first random fiber laser and a novel
quasi-one-dimensional RL geometry. Comparison with similar systems in bulk
format shows that the random fiber laser presents an efficiency that is at
least two orders of magnitude higher.
| [
{
"version": "v1",
"created": "Fri, 29 Jun 2007 15:38:39 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"de Matos",
"Christiano J. S.",
""
],
[
"Menezes",
"Leonardo de S.",
""
],
[
"Brito-Silva",
"Antônio M.",
""
],
[
"Gámez",
"M. A. Martinez",
""
],
[
"Gomes",
"Anderson S. L.",
""
],
[
"de Araújo",
"Cid B.",
""
]
] |
0706.4446 | Sandra Martinez | Sandra Martinez | An optimization problem with volume constrain in Orlicz spaces | null | null | 10.1016/j.jmaa.2007.09.061 | null | math.AP | null | We consider the optimization problem of minimizing $\int_{\Omega}G(|\nabla
u|) dx$ in the class of functions $W^{1,G}(\Omega)$, with a constrain on the
volume of $\{u>0\}$. The conditions on the function $G$ allow for a different
behavior at
0 and at $\infty$. We consider a penalization problem, and we prove that for
small values of the penalization parameter, the constrained volume is attained.
In this way we prove that every solution $u$ is locally Lipschitz continuous
and that the free boundary, $\partial\{u>0\}\cap \Omega$, is smooth.
| [
{
"version": "v1",
"created": "Fri, 29 Jun 2007 15:41:36 GMT"
},
{
"version": "v2",
"created": "Tue, 10 Jul 2007 14:14:55 GMT"
}
] | 2015-05-13T00:00:00 | [
[
"Martinez",
"Sandra",
""
]
] |
0706.4447 | J. Wildeshaus | J. Wildeshaus | Pure motives, mixed motives and extensions of motives associated to
singular surfaces | 40 pages; final version | Panor. Synth. (SMF) 49 (2016), 65-100 | null | null | math.KT math.AG | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We first recall the construction of the Chow motive modelling intersection
cohomology of a proper surface and study its fundamental properties. Using
Voevodsky's category of effective geometrical motives, we then study the motive
of the exceptional divisor in a non-singular blow-up. If all geometric
irreducible components of the divisor are of genus zero, then Voevodsky's
formalism allows us to construct certain one-extensions of Chow motives, as
canonical sub-quotients of the motive with compact support of the smooth part
of the surface. Specializing to Hilbert--Blumenthal surfaces, we recover a
motivic interpretation of a recent construction of A. Caspar.
| [
{
"version": "v1",
"created": "Fri, 29 Jun 2007 15:45:54 GMT"
},
{
"version": "v2",
"created": "Fri, 21 Dec 2007 17:34:41 GMT"
},
{
"version": "v3",
"created": "Fri, 29 Jan 2010 19:17:44 GMT"
},
{
"version": "v4",
"created": "Thu, 19 May 2011 10:50:57 GMT"
}
] | 2017-06-23T00:00:00 | [
[
"Wildeshaus",
"J.",
""
]
] |
0706.4448 | Alon Attal | CDF Collaboration, A. Abulencia, et al | Search for Anomalous Production of Multilepton Events in p-pbar
Collisions at sqrt(s) = 1.96 TeV | 1 revtex file, 3 eps figures, 1 author list, 4 files needed for
revtex (for completeness) | Phys.Rev.Lett.98:131804,2007 | 10.1103/PhysRevLett.98.131804 | null | hep-ex | null | We report a search for the anomalous production of events with multiple
charged leptons in p-pbar collisions at sqrt{s} = 1.96 TeV using a data sample
corresponding to an integrated luminosity of 346 pb^{-1} collected by the CDF
II detector at the Fermilab Tevatron. The search is divided into three-lepton
and four-or-more-lepton data samples. We observe six events in the three-lepton
sample and zero events in the >=4-lepton sample. Both numbers of events are
consistent with standard model background expectations. Within the framework of
an R-parity violating supergravity model, the results are interpreted as mass
limits on the lightest neutralino and chargino particles. For one particular
choice of model parameters, the limits are M_neutralino > 110 GeV/c^{2} and
M_chargino > 203 GeV/c^{2} at 95% confidence level; the variation of these mass
limits with model parameters is presented.
| [
{
"version": "v1",
"created": "Fri, 29 Jun 2007 15:54:04 GMT"
}
] | 2010-05-12T00:00:00 | [
[
"CDF Collaboration",
"",
""
],
[
"Abulencia",
"A.",
""
]
] |
0706.4449 | Panos Papasoglu | Panos Papasoglu | Cheeger constants of surfaces and isoperimetric inequalities | 28 pages | null | null | null | math.DG math.GR math.GT math.MG | null | We show that the Cheeger constant of compact surfaces is bounded by a
function of the area. We apply this to isoperimetric profiles of bounded genus
non-compact surfaces, to show that if their isoperimetric profile grows faster
than $\sqrt t$, then it grows at least as fast as a linear function. This
generalizes a result of Gromov for simply connected surfaces.
We study the isoperimetric problem in dimension 3. We show that if the
filling volume function in dimension 2 is Euclidean, while in dimension 3 is
sub-Euclidean and there is a $g$ such that minimizers in dimension 3 have genus
at most $g$, then the filling function in dimension 3 is `almost' linear.
| [
{
"version": "v1",
"created": "Fri, 29 Jun 2007 15:48:44 GMT"
}
] | 2007-07-02T00:00:00 | [
[
"Papasoglu",
"Panos",
""
]
] |
0706.4450 | Gilles Pages | Gilles Pag\`es (PMA) | Quadratic optimal functional quantization of stochastic processes and
numerical applications | 41 pages | null | 10.1007/978-3-540-74496-2_6 | null | math.PR | null | In this paper, we present an overview of the recent developments of
functional quantization of stochastic processes, with an emphasis on the
quadratic case. Functional quantization is a way to approximate a process,
viewed as a Hilbert-valued random variable, using a nearest neighbour
projection on a finite codebook. A special emphasis is made on the
computational aspects and the numerical applications, in particular the pricing
of some path-dependent European options.
| [
{
"version": "v1",
"created": "Fri, 29 Jun 2007 15:53:27 GMT"
}
] | 2013-04-03T00:00:00 | [
[
"Pagès",
"Gilles",
"",
"PMA"
]
] |
0706.4451 | Victor Yakhot | Victor Yakhot | Turbulence models generator | null | null | null | null | nlin.CG physics.flu-dyn | null | In this paper we explore a possibility that all transport turbulent models
are contained in a coarse-grained kinetic equation. Building on a recent work
by H.Chen et al (2004), we account for fluctuations of a single -point
probability density in turbulence, by introducing a``two-level'' (${\bf
c,v}$)-phase-space, separating microscopic (${\bf c'\equiv c_{micro}= c-v}$)
and hydrodynamic (${\bf v'=v-V}$) modes. Unlike traditional kinetic theories,
with hydrodynamic approximations derived in terms of small deviations from
thermodynamic equilibrium, the theory developed in this work, is based on a
far- from -equilibrium isotropic and homogeneous turbulence as an unperturbed
state. The expansion in dimensionless rate of strain leads to a new class of
turbulent models, including the well-known ${\cal K}-{\cal E}$, Reynolds stress
and all possible nonlinear models. The role of interaction of the fluxes in
physical space with the energy flux across the scales, not present in standard
modeling, is demonstrated on example of turbulent channel flow. To close the
system, neither equation for turbulent kinetic energy nor information on
pressure-velocity correlations, contained in the derived coarse-grained kinetic
equation, are needed.
| [
{
"version": "v1",
"created": "Fri, 29 Jun 2007 15:55:02 GMT"
}
] | 2007-07-05T00:00:00 | [
[
"Yakhot",
"Victor",
""
]
] |
0706.4452 | Louis Crane | Louis Crane | What is the Mathematical Structure of Quantum Spacetime? | 25 pages, latex file | null | null | null | gr-qc | null | We survey indications from different branches of Physics that the fine scale
structure of spacetime is not adequately described by a manifold. Based on the
hints we accumulate, we propose a new structure, which we call a quantum topos.
In the process of constructing a quantum topos for quantum gravity, we propose
a new, operational approach to the problem of the obervables in quantum
gravity, which leads to a new mathematical point of view on the state sum
models.
| [
{
"version": "v1",
"created": "Fri, 29 Jun 2007 16:01:03 GMT"
}
] | 2007-07-02T00:00:00 | [
[
"Crane",
"Louis",
""
]
] |
0706.4453 | Markus Meyer | M. Meyer (for the MAGIC Collaboration: J. Albert, et al.) | Systematic search for VHE gamma-ray emission from X-ray bright
high-frequency BL Lac objects | 15 pages, 7 figures, 5 tables, submitted to ApJ (revised version) | Astrophys.J.681:944-953,2008 | 10.1086/587499 | null | astro-ph | null | All but three (M87, BL Lac and 3C 279) extragalactic sources detected so far
at very high energy (VHE) gamma-rays belong to the class of high-frequency
peaked BL Lac (HBL) objects. This suggested to us a systematic scan of
candidate sources with the MAGIC telescope, based on the compilation of X-ray
blazars by Donato et al. (2001). The observations took place from December 2004
to March 2006 and cover sources on the northern sky visible under small zenith
distances zd < 30 degrees at culmination. The sensitivity of the search was
planned for detecting X-ray bright F(1 keV) > 2 uJy) sources emitting at least
the same energy flux at 200 GeV as at 1 keV. In order to avoid strong gamma-ray
attenuation close to the energy threshold, the redshift of the sources was
constrained to values z<0.3. Of the fourteen sources observed, 1ES 1218+304 and
1ES 2344+514 have been detected in addition to the known bright TeV blazars Mrk
421 and Mrk 501. A marginal excess of 3.5 sigma from the position of 1ES
1011+496 was observed and has been confirmed as a source of VHE gamma-rays by a
second MAGIC observation triggered by a high optical state (Albert et al.
2007). For the remaining sources, we present here the 99% confidence level
upper limits on the integral flux above ~200 GeV. We characterize the sample of
HBLs (including all HBLs detected at VHE so far) by looking for correlations
between their multi-frequency spectral indices determined from simultaneous
optical, archival X-ray, and radio luminosities, finding that the VHE emitting
HBLs do not seem to constitute a unique subclass. The absorption corrected
gamma-ray luminosities at 200 GeV of the HBLs are generally not higher than
their X-ray luminosities at 1 keV.
| [
{
"version": "v1",
"created": "Fri, 29 Jun 2007 17:38:38 GMT"
},
{
"version": "v2",
"created": "Fri, 21 Dec 2007 10:26:39 GMT"
}
] | 2019-08-12T00:00:00 | [
[
"Meyer",
"M.",
"",
"for the MAGIC Collaboration: J. Albert, et al."
]
] |
0706.4454 | Ernest Barreto | Ernest Barreto (1), Brian Hunt (2), Edward Ott (2), and Paul So (1)
((1) George Mason University, (2) University of Maryland) | Synchronization in networks of networks: the onset of coherent
collective behavior in systems of interacting populations of heterogeneous
oscillators | The original was replaced with a version that has been accepted to
Phys. Rev. E. The new version has the same content, but the title, abstract,
and the introductory text have been revised | null | 10.1103/PhysRevE.77.036107 | null | math.DS | null | The onset of synchronization in networks of networks is investigated.
Specifically, we consider networks of interacting phase oscillators in which
the set of oscillators is composed of several distinct populations. The
oscillators in a given population are heterogeneous in that their natural
frequencies are drawn from a given distribution, and each population has its
own such distribution. The coupling among the oscillators is global, however,
we permit the coupling strengths between the members of different populations
to be separately specified. We determine the critical condition for the onset
of coherent collective behavior, and develop the illustrative case in which the
oscillator frequencies are drawn from a set of (possibly different)
Cauchy-Lorentz distributions. One motivation is drawn from neurobiology, in
which the collective dynamics of several interacting populations of oscillators
(such as excitatory and inhibitory neurons and glia) are of interest.
| [
{
"version": "v1",
"created": "Fri, 29 Jun 2007 16:11:34 GMT"
},
{
"version": "v2",
"created": "Thu, 24 Jan 2008 17:17:00 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Barreto",
"Ernest",
"",
"George Mason University"
],
[
"Hunt",
"Brian",
"",
"University of Maryland"
],
[
"Ott",
"Edward",
"",
"University of Maryland"
],
[
"So",
"Paul",
"",
"George Mason University"
]
] |
0706.4455 | Nan Lin Wang | G. Li, W. Z. Hu, J. Dong, D. Qian, D. Hsieh, M. Z. Hasan, E. Morosan,
R. J. Cava, N. L. Wang | Anomalous metallic state of Cu$_{0.07}$TiSe$_2$: an optical spectroscopy
study | 4 figures, 4+ pages | Phys. Rev. Lett. 99, 167002 (2007) | 10.1103/PhysRevLett.99.167002 | null | cond-mat.supr-con cond-mat.str-el | null | We report an optical spectroscopy study on the newly discovered
superconductor Cu$_{0.07}$TiSe$_2$. Consistent with the development from a
semimetal or semiconductor with a very small indirect energy gap upon doping
TiSe$_2$, it is found that the compound has a low carrier density. Most
remarkably, the study reveals a substantial shift of the "screened" plasma edge
in reflectance towards high energy with decreasing temperature. This
phenomenon, rarely seen in metals, indicates either a sizeable increase of the
conducting carrier concentration or/and a decrease of the effective mass of
carriers with reducing temperature. We attribute the shift primarily to the
later effect.
| [
{
"version": "v1",
"created": "Fri, 29 Jun 2007 16:11:51 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Li",
"G.",
""
],
[
"Hu",
"W. Z.",
""
],
[
"Dong",
"J.",
""
],
[
"Qian",
"D.",
""
],
[
"Hsieh",
"D.",
""
],
[
"Hasan",
"M. Z.",
""
],
[
"Morosan",
"E.",
""
],
[
"Cava",
"R. J.",
""
],
[
"Wang",
"N. L.",
""
]
] |
0706.4456 | Hendrik van Hees | H. van Hees, V. Greco and R. Rapp | Heavy-Quark Kinetics in the QGP at LHC | 2 pages, 6 figures. Contributed to Workshop on Heavy Ion Collisions
at the LHC: Last Call for Predictions, Geneva, Switzerland, 14 May - 8 Jun
2007 v2: acknowledgment included | Journal of Physics G 35, 1 (2008), p 125 | 10.1088/0954-3899/35/5/054001 | null | hep-ph nucl-ex nucl-th | null | We present predictions for the nuclear modification factor and elliptic flow
of D and B mesons, as well as of their decay electrons, in semicentral Pb-Pb
collisions at the LHC. Heavy quarks are propagated in a Quark-Gluon Plasma
using a relativistic Langevin simulation with drag and diffusion coefficients
from elastic interactions with light anti-/quarks and gluons, including
non-perturbative resonance scattering. Hadronization at T_c is performed within
a combined coalescence-fragmentation scheme.
| [
{
"version": "v1",
"created": "Fri, 29 Jun 2007 16:29:45 GMT"
},
{
"version": "v2",
"created": "Sat, 30 Jun 2007 22:26:23 GMT"
}
] | 2008-04-22T00:00:00 | [
[
"van Hees",
"H.",
""
],
[
"Greco",
"V.",
""
],
[
"Rapp",
"R.",
""
]
] |
0706.4457 | Victor Yakhot | Victor Yakhot | Dissipation Scale Fluctuations and Chemical Reaction Rates in Turbulent
Flows | null | null | 10.1017/S0022112008001791 | null | nlin.CD astro-ph physics.flu-dyn | null | Small separation between reactants, not exceeding $10^{-8}-10^{-7}cm$, is the
necessary condition for various chemical reactions. It is shown that random
advection and stretching by turbulence leads to formation of scalar-enriched
sheets of {\it strongly fluctuating thickness} $\eta_{c}$. The molecular-level
mixing is achieved by diffusion across these sheets (interfaces) separating the
reactants. Since diffusion time scale is $\tau_{d}\propto \eta_{c}^{2}$, the
knowledge of probability density $Q(\eta_{c},Re)$ is crucial for evaluation of
chemical reaction rates. In this paper we derive the probability density
$Q(\eta_{c},Re,Sc)$ and predict a transition in the reaction rate behavior from
${\cal R}\propto \sqrt{Re}$ ($Re\leq 10^{4}$) to the high-Re asymptotics ${\cal
R}\propto Re^{0}$. The theory leads to an approximate universality of
transitional Reynolds number $Re_{tr}\approx 10^{4}$. It is also shown that if
chemical reaction involves short-lived reactants, very strong anomalous
fluctuations of the length-scale $\eta_{c}$ may lead to non-negligibly small
reaction rates.
| [
{
"version": "v1",
"created": "Fri, 29 Jun 2007 16:30:06 GMT"
}
] | 2015-05-13T00:00:00 | [
[
"Yakhot",
"Victor",
""
]
] |
0706.4458 | Marco Porta | Marco Porta | The Popescu-Gabriel theorem for triangulated categories | 32 pages; submitted to Advances in Mathematics; one reference added | null | null | null | math.KT | null | The Popescu-Gabriel theorem states that each Grothendieck abelian category is
a localization of a module category. In this paper, we prove an analogue where
Grothendieck abelian categories are replaced by triangulated categories which
are well generated (in the sense of Neeman) and algebraic (in the sense of
Keller). The role of module categories is played by derived categories of small
differential graded categories. An analogous result for topological
triangulated categories has recently been obtained by A. Heider.
| [
{
"version": "v1",
"created": "Fri, 29 Jun 2007 17:08:55 GMT"
},
{
"version": "v2",
"created": "Fri, 15 Feb 2008 16:16:17 GMT"
}
] | 2008-02-15T00:00:00 | [
[
"Porta",
"Marco",
""
]
] |
0706.4459 | Fabio Natali | F. Natali | A note on the stability for Kawahara-KdV type equations | 8 pages, no figures | null | null | null | math.AP | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In this paper we establish the nonlinear stability of solitary traveling-wave
solutions for the Kawahara-KdV equation $$u_t+uu_x+u_{xxx}-\gamma_1
u_{xxxxx}=0,$$ and the modified Kawahara-KdV equation
$$u_t+3u^2u_x+u_{xxx}-\gamma_2 u_{xxxxx}=0,$$ where $\gamma_i\in\mathbb{R}$ is
a positive number when $i=1,2$. The main approach used to determine the
stability of solitary traveling-waves will be the theory developed by Albert
| [
{
"version": "v1",
"created": "Fri, 29 Jun 2007 16:42:39 GMT"
},
{
"version": "v2",
"created": "Mon, 13 Jul 2009 11:45:47 GMT"
}
] | 2009-07-13T00:00:00 | [
[
"Natali",
"F.",
""
]
] |
0706.4460 | Olivera Miskovic | Olivera Miskovic and Rodrigo Olea | Counterterms in Dimensionally Continued AdS Gravity | 26 pages, no figures; references added; version accepted for
publication in JHEP | JHEP 0710:028,2007 | 10.1088/1126-6708/2007/10/028 | IFUM-896-FT | hep-th gr-qc | null | We revise two regularization mechanisms for Lovelock gravity with AdS
asymptotics. The first one corresponds to the Dirichlet counterterm method,
where local functionals of the boundary metric are added to the bulk action on
top of a Gibbons-Hawking-Myers term that defines the Dirichlet problem in
gravity. The generalized Gibbons-Hawking term can be found in any Lovelock
theory following the Myers' procedure to achieve a well-posed action principle
for a Dirichlet boundary condition on the metric, which is proved to be
equivalent to the Hamiltonian formulation for a radial foliation of spacetime.
In turn, a closed expression for the Dirichlet counterterms does not exist for
a generic Lovelock gravity. The second method supplements the bulk action with
boundary terms which depend on the extrinsic curvature (Kounterterms), and
whose explicit form is independent of the particular theory considered.
In this paper, we use Dimensionally Continued AdS Gravity (Chern-Simons-AdS
in odd and Born-Infeld-AdS in even dimensions) as a toy model to perform the
first explicit comparison between both regularization prescriptions. This can
be done thanks to the fact that, in this theory, the Dirichlet counterterms can
be readily integrated out from the divergent part of the Dirichlet variation of
the action.
The agreement between both procedures at the level of the boundary terms
suggests the existence of a general property of any Lovelock-AdS gravity:
intrinsic counterterms are generated as the difference between the Kounterterm
series and the corresponding Gibbons-Hawking-Myers term.
| [
{
"version": "v1",
"created": "Fri, 29 Jun 2007 16:48:34 GMT"
},
{
"version": "v2",
"created": "Wed, 26 Sep 2007 18:56:30 GMT"
},
{
"version": "v3",
"created": "Mon, 1 Oct 2007 20:24:14 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Miskovic",
"Olivera",
""
],
[
"Olea",
"Rodrigo",
""
]
] |
0706.4461 | Kelsey E. Johnson | K.E. Johnson, J.E. Hibbard, S.C. Gallagher, J.C. Charlton, A.E.
Hornschemeier, T.H. Jarrett, A.E. Reines | The Infrared Properties of Hickson Compact Groups | 34 pages, 26 figures, accepted for publication in AJ, higher quality
images available in publication | Astron.J.134:1522-1543,2007 | 10.1086/520921 | null | astro-ph | null | Compact groups of galaxies provide a unique environment to study the
mechanisms by which star formation occurs amid continuous gravitational
encounters. We present 2MASS (JHK), Spitzer IRAC (3.5-8 micron) and MIPS (24
micron) observations of a sample of twelve Hickson Compact Groups (HCGs 2, 7,
16, 19, 22, 31, 42, 48, 59, 61, 62, and 90) that includes a total of 45
galaxies. The near-infrared colors of the sample galaxies are largely
consistent with being dominated by slightly reddened normal stellar
populations. Galaxies that have the most significant PAH and/or hot dust
emission (as inferred from excess 8 micron flux) also tend to have larger
amounts of extinction and/or K-band excess and stronger 24 micron emission, all
of which suggest ongoing star formation activity. We separate the twelve HCGs
in our sample into three types based on the ratio of the group HI mass to
dynamical mass. We find evidence that galaxies in the most gas-rich groups tend
to be the most actively star forming. Galaxies in the most gas-poor groups tend
to be tightly clustered around a narrow range in colors consistent with the
integrated light from a normal stellar population. We interpret these trends as
indicating that galaxies in gas-rich groups experience star formation and/or
nuclear actively until their neutral gas consumed, stripped, or ionized. The
galaxies in this sample exhibit a ``gap'' between gas-rich and gas-poor groups
in infrared color space that is sparsely populated and not seen in the Spitzer
First Look Survey sample. This gap may suggest a rapid evolution of galaxy
properties in response to dynamical effects. These results suggest that the
global properties of the groups and the local properties of the galaxies are
connected.
| [
{
"version": "v1",
"created": "Fri, 29 Jun 2007 19:01:25 GMT"
},
{
"version": "v2",
"created": "Tue, 10 Jul 2007 18:31:01 GMT"
}
] | 2008-11-26T00:00:00 | [
[
"Johnson",
"K. E.",
""
],
[
"Hibbard",
"J. E.",
""
],
[
"Gallagher",
"S. C.",
""
],
[
"Charlton",
"J. C.",
""
],
[
"Hornschemeier",
"A. E.",
""
],
[
"Jarrett",
"T. H.",
""
],
[
"Reines",
"A. E.",
""
]
] |
0706.4462 | Shimul Akhanjee | Shimul Akhanjee and Joseph Rudnick | Disorder induced transition into a one-dimensional Wigner glass | 5 pages, revtex. Typo regarding localization length exponent
corrected. Should read 1 / \delta | Phys. Rev. Lett. 99, 236403 (2007) | 10.1103/PhysRevLett.99.236403 | null | cond-mat.dis-nn cond-mat.str-el | null | The destruction of quasi-long range crystalline order as a consequence of
strong disorder effects is shown to accompany the strict localization of all
classical plasma modes of one-dimensional Wigner crystals at T=0. We construct
a phase diagram that relates the structural phase properties of Wigner crystals
to a plasmon delocalization transition recently reported. Deep inside the
strictly localized phase of the strong disorder regime, we observe
``glass-like'' behavior. However, well into the critical phase with a plasmon
mobility edge, the system retains its crystalline composition. We predict that
a transition between the two phases occurs at a critical value of the relative
disorder strength. This transition has an experimental signature in the AC
conductivity as a local maximum of the largest spectral amplitude as a function
of the relative disorder strength.
| [
{
"version": "v1",
"created": "Fri, 29 Jun 2007 18:47:05 GMT"
},
{
"version": "v2",
"created": "Thu, 25 Oct 2007 03:40:55 GMT"
},
{
"version": "v3",
"created": "Mon, 2 Jun 2008 07:24:46 GMT"
}
] | 2008-06-02T00:00:00 | [
[
"Akhanjee",
"Shimul",
""
],
[
"Rudnick",
"Joseph",
""
]
] |
0706.4463 | Evy Kersal\'e | Evy Kersale, David W. Hughes, Steven M. Tobias | The Nonlinear Evolution of Instabilities Driven by Magnetic Buoyancy: A
New Mechanism for the Formation of Coherent Magnetic Structures | Published in ApJL. Version with colour figures | Astrophys.J.663:L113-L116,2007 | 10.1086/520339 | null | astro-ph | null | Motivated by the problem of the formation of active regions from a
deep-seated solar magnetic field, we consider the nonlinear three-dimensional
evolution of magnetic buoyancy instabilities resulting from a smoothly
stratified horizontal magnetic field. By exploring the case for which the
instability is continuously driven we have identified a new mechanism for the
formation of concentrations of magnetic flux.
| [
{
"version": "v1",
"created": "Fri, 29 Jun 2007 17:15:15 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Kersale",
"Evy",
""
],
[
"Hughes",
"David W.",
""
],
[
"Tobias",
"Steven M.",
""
]
] |
0706.4464 | Stephen Hayden | O.J. Lipscombe, S.M. Hayden, B. Vignolle, D.F. McMorrow, T.G. Perring | The Persistence of High-Frequency Spin Fluctuations in Overdoped
La$_{2-x}$Sr$_{x}$CuO$_{4}$ ($x$=0.22) | 4 pages, 4 figures | Phys. Rev. Lett. 99, 067002 (2007) | 10.1103/PhysRevLett.99.067002 | null | cond-mat.supr-con cond-mat.str-el | null | We report a detailed inelastic neutron scattering study of the collective
magnetic excitations of overdoped superconducting La1.78Sr0.22CuO4 for the
energy range 0-160 meV. Our measurements show that overdoping suppresses the
strong response present for optimally doped La2-xSrxCuO4 which is peaked near
50 meV. The remaining response is peaked at incommensurate wavevectors for all
energies investigated. We observe a strong high-frequency magnetic response for
E >= 80 meV suggesting that significant antiferromagnetic exchange couplings
persist well into the overdoped part of the cuprate phase diagram.
| [
{
"version": "v1",
"created": "Fri, 29 Jun 2007 17:23:56 GMT"
}
] | 2007-09-04T00:00:00 | [
[
"Lipscombe",
"O. J.",
""
],
[
"Hayden",
"S. M.",
""
],
[
"Vignolle",
"B.",
""
],
[
"McMorrow",
"D. F.",
""
],
[
"Perring",
"T. G.",
""
]
] |
0706.4465 | Jinfeng Liao | Jinfeng Liao and Edward Shuryak | Electric Flux Tube in Magnetic Plasma | New version with new referecences added and minor changes. 15 pages,
8 figures | Phys.Rev.C77:064905,2008 | 10.1103/PhysRevC.77.064905 | null | hep-ph | null | In this paper we study a methodical problem related to the magnetic scenario
recently suggested and initiated by the authors \cite{Liao_ES_mono} to
understand the strongly coupled quark-gluon plasma (sQGP): the electric flux
tube in monopole plasma. A macroscopic approach, interpolating between Bose
condensed (dual superconductor) and classical gas medium is developed first.
Then we work out a microscopic approach based on detailed quantum mechanical
calculation of the monopole scattering on electric flux tube, evaluating
induced currents for all partial waves. As expected, the flux tube looses its
stability when particles can penetrate it: we make this condition precise by
calculating the critical value for the product of the flux tube size times the
particle momentum, above which the flux tube dissolves. Lattice static
potentials indicate that flux tubes seem to dissolve at $T>T_{dissolution}
\approx 1.3 T_c$. Using our criterion one gets an estimate of the magnetic
density $n\approx 4.4 \sim 6.6 fm^{-3}$ at this temperature.
| [
{
"version": "v1",
"created": "Fri, 29 Jun 2007 17:24:38 GMT"
},
{
"version": "v2",
"created": "Sat, 29 Sep 2007 04:08:52 GMT"
},
{
"version": "v3",
"created": "Thu, 6 Dec 2007 22:21:58 GMT"
}
] | 2010-05-27T00:00:00 | [
[
"Liao",
"Jinfeng",
""
],
[
"Shuryak",
"Edward",
""
]
] |
0706.4466 | Francisco J. Cao | F. J. Cao, M. Feito | Flux enhancement and multistability induced by time delays in a feedback
controlled flashing ratchet | LaTeX, 6 pages, 5 figures. Material added to arXiv:0706.1496 and
published in Phys. Rev. E | null | null | null | cond-mat.stat-mech | null | Feedback controlled ratchets are thermal rectifiers that use information on
the state of the system to operate. We study the effects of time delays in the
feedback for a protocol that performs an instantaneous maximization of the
center-of-mass velocity in the many particle case. For small delays the
center-of-mass velocity decreases for increasing delays (although not as fast
as in the few particle case). However, for large delays we find the surprising
result that the presence of a delay can improve the flux performance of the
ratchet. In fact, the maximum flux obtained with the optimal periodic protocol
is attained. This implies that the delayed feedback protocol considered can
perform better than its non-delayed counterpart. The improvement of the flux
observed in the presence of large delays is the result of the emergence of a
new dynamical regime where the presence of the delayed feedback stabilizes
quasiperiodic solutions that resemble the solutions obtained in a certain
closed-loop protocol with thresholds. In addition, in this new regime the
system presents multistability, i.e. several quasiperiodic solutions can be
stable for a fixed time delay.
| [
{
"version": "v1",
"created": "Fri, 29 Jun 2007 17:44:45 GMT"
},
{
"version": "v2",
"created": "Sun, 13 Apr 2008 10:07:35 GMT"
}
] | 2008-04-13T00:00:00 | [
[
"Cao",
"F. J.",
""
],
[
"Feito",
"M.",
""
]
] |
0706.4467 | Michele Cantiello | Michele Cantiello (1,2), John P. Blakeslee (1), Gabriella Raimondo
(2), Enzo Brocato (1), Massimo Capaccioli (3) ((1) Department of Physics,
Astronomy, Washington State University, Pullman, (2) INAF--Osservatorio
Astronomico di Teramo, (3) Dipartimento di Scienze Fisiche, Universita'
Federico I. I. di Napoli) | Surface Brightness Fluctuations from archival ACS images: a stellar
population and distance study | ApJ Accepted | null | 10.1086/521295 | null | astro-ph | null | We derive Surface Brightness Fluctuations (SBF) and integrated magnitudes in
the V- and I-bands using Advanced Camera for Surveys (ACS) archival data. The
sample includes 14 galaxies covering a wide range of physical properties:
morphology, total absolute magnitude, integrated color. We take advantage of
the latter characteristic of the sample to check existing empirical
calibrations of absolute SBF magnitudes both in the I- and V-passbands.
Additionally, by comparing our SBF and color data with the Teramo-SPoT simple
stellar population models, and other recent sets of population synthesis
models, we discuss the feasibility of stellar population studies based on
fluctuation magnitudes analysis. The main result of this study is that
multiband optical SBF data and integrated colors can be used to significantly
constrain the chemical composition of the dominant stellar system in the
galaxy, but not the age in the case of systems older than 3 Gyr.
SBF color gradients are also detected and analyzed. These SBF gradient data,
together with other available data, point to the existence of mass dependent
metallicity gradients in galaxies, with the more massive objects showing a
non--negligible SBF versus color gradient. The comparison with models suggests
that such gradients imply more metal rich stellar populations in the galaxies'
inner regions with respect to the outer ones.
| [
{
"version": "v1",
"created": "Fri, 29 Jun 2007 17:39:11 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Cantiello",
"Michele",
""
],
[
"Blakeslee",
"John P.",
""
],
[
"Raimondo",
"Gabriella",
""
],
[
"Brocato",
"Enzo",
""
],
[
"Capaccioli",
"Massimo",
""
]
] |
0706.4468 | Armin Hauke | Armin Hauke | Experimental Results on |Vcb| and b -> c l nu Transitions | 10 pages, 12 figures, Flavor Physics & CP Violation Conference, Bled,
2007 | ECONFC070512:017,2007 | null | SLAC-PUB-12651 | hep-ex | null | A review of recent analyses on semileptonic decays of B mesons into charmed
final states is given. |Vcb| is extracted both by the Babar and the Belle
collaboration from their datasets using inclusively and exclusively
reconstructed final states.
In addition there are recent results on the determination of exclusive
branching fractions to the ground states D and D*, as well as to excited D**
states. Those play an important role in understanding the composition of the
total decay width. They represent also a sizable fraction of the backgrounds
for exclusive analyses and are presented here as well.
| [
{
"version": "v1",
"created": "Fri, 29 Jun 2007 17:46:47 GMT"
}
] | 2008-11-26T00:00:00 | [
[
"Hauke",
"Armin",
""
]
] |
0706.4469 | Adrian E. Feiguin | A. E. Feiguin, E. Rezayi, C. Nayak, S. Das Sarma | Density Matrix Renormalization Group Study of Incompressible Fractional
Quantum Hall States | 5 pages, 4 figures | Phys. Rev. Lett. 100, 166803 (2008) | 10.1103/PhysRevLett.100.166803 | null | cond-mat.mes-hall cond-mat.str-el | null | We develop the Density Matrix Renormalization Group (DMRG) technique for
numerically studying incompressible fractional quantum Hall (FQH) states on the
sphere. We calculate accurate estimates for ground state energies and
excitationgaps at FQH filling fractions \nu=1/3 and \nu=5/2 for systems that
are almost twice as large as the largest ever studied by exact diagonalization.
We establish, by carefully comparing with existing numerical results on smaller
systems, that DMRG is a highly effective numerical tool for studying
incompressible FQH states.
| [
{
"version": "v1",
"created": "Fri, 29 Jun 2007 17:51:42 GMT"
},
{
"version": "v2",
"created": "Fri, 13 Jul 2007 16:05:25 GMT"
}
] | 2009-07-21T00:00:00 | [
[
"Feiguin",
"A. E.",
""
],
[
"Rezayi",
"E.",
""
],
[
"Nayak",
"C.",
""
],
[
"Sarma",
"S. Das",
""
]
] |
0706.4470 | Claudio Pica | G.Cossu, M.D'Elia, A.Di Giacomo and C.Pica | Two flavor QCD and confinement - II | 7 pages, 6 figures | null | null | BNL-NT-07/30, IFUP-TH/2007-14, GEF-TH-03-07 | hep-lat | null | This paper is part of a program of investigation of the chiral transition in
Nf=2 QCD, started in Phys.Rev.D72:114510,2005. Progress is reported on the
understanding of some possible systematic errors. A direct test of first order
scaling is presented.
| [
{
"version": "v1",
"created": "Fri, 29 Jun 2007 18:07:06 GMT"
}
] | 2007-07-02T00:00:00 | [
[
"Cossu",
"G.",
""
],
[
"D'Elia",
"M.",
""
],
[
"Di Giacomo",
"A.",
""
],
[
"Pica",
"C.",
""
]
] |
0706.4471 | Hirotaka Irie | Hirotaka Irie | Notes on D-branes and dualities in (p,q) minimal superstring theory | 34 pages; v2: Grammatical errors corrected, minor change; v3:
references added | Nucl.Phys.B794:402-428,2008 | 10.1016/j.nuclphysb.2007.09.015 | KUNS-2072 | hep-th | null | We study boundary states in (p,q) minimal superstring theory, combining the
explicit form of matter wave functions. Within the modular bootstrap framework,
Cardy states of (p,q) minimal superconformal field theory are completely
determined in both cases of the different supercharge combinations, and the
remaining consistency checks in the super-Liouville case are also performed.
Using these boundary states, we determine the explicit form of FZZT- and
ZZ-brane boundary states both in type 0A and 0B GSO projections. Annulus
mplitudes of FZZT branes are evaluated and principal FZZT branes are
identified. In particular, we found that these principal FZZT branes do not
satisfy Cardy's consistency conditions for each other and play a role of
order/disorder parameters of the Kramers-Wannier duality in spacetime of this
superstring theory.
| [
{
"version": "v1",
"created": "Fri, 29 Jun 2007 19:56:06 GMT"
},
{
"version": "v2",
"created": "Sat, 22 Sep 2007 14:10:10 GMT"
},
{
"version": "v3",
"created": "Mon, 3 Mar 2008 12:03:46 GMT"
}
] | 2008-11-26T00:00:00 | [
[
"Irie",
"Hirotaka",
""
]
] |
0706.4472 | Georgi Medvedev | Georgi S. Medvedev and Yun Yoo | Chaos at the border of criticality | Chaos: An Interdisciplinary Journal of Nonlinear Science
(tentatively, Sept 2008) | null | 10.1063/1.2953586 | null | nlin.CD | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The present paper points out to a novel scenario for formation of chaotic
attractors in a class of models of excitable cell membranes near an
Andronov-Hopf bifurcation (AHB). The mechanism underlying chaotic dynamics
admits a simple and visual description in terms of the families of
one-dimensional first-return maps, which are constructed using the combination
of asymptotic and numerical techniques. The bifurcation structure of the
continuous system (specifically, the proximity to a degenerate AHB) endows the
Poincare map with distinct qualitative features such as unimodality and the
presence of the boundary layer, where the map is strongly expanding. This
structure of the map in turn explains the bifurcation scenarios in the
continuous system including chaotic mixed-mode oscillations near the border
between the regions of sub- and supercritical AHB. The proposed mechanism
yields the statistical properties of the mixed-mode oscillations in this
regime. The statistics predicted by the analysis of the Poincare map and those
observed in the numerical experiments of the continuous system show a very good
agreement.
| [
{
"version": "v1",
"created": "Fri, 29 Jun 2007 18:13:49 GMT"
},
{
"version": "v2",
"created": "Fri, 13 Jun 2008 15:52:16 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Medvedev",
"Georgi S.",
""
],
[
"Yoo",
"Yun",
""
]
] |
0706.4473 | Andriy Haydys | Andriy Haydys | HyperKahler and quaternionic Kahler manifolds with S^1-symmetries | 24 pages; section 4 is new; new examples added | null | 10.1016/j.geomphys.2007.11.004 | null | math.DG math-ph math.MP | null | We study relations between quaternionic Riemannian manifolds admitting
different types of symmetries. We show that any hyperKahler manifold admitting
hyperKahler potential and triholomorphic action of S^1 can be constructed from
another hyperKahler manifold (of lower dimention) with an action of S^1 which
fixes one complex structure and rotates the other two and vice versa. We also
study corresponding quaternionic Kahler manifolds equipped with a quaternionic
Kahler action of the circle. In particular we show that any positive
quaternionic Kahler manifold with S^1 symmetry admits a Kahler metric on an
open everywhere dense subset.
| [
{
"version": "v1",
"created": "Fri, 29 Jun 2007 18:24:54 GMT"
},
{
"version": "v2",
"created": "Thu, 13 Sep 2007 17:27:40 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Haydys",
"Andriy",
""
]
] |
0706.4474 | Nikodem Poplawski | Nikodem J. Poplawski | F(R) gravity in purely affine formulation | 7 pages; published version | Int.J.Mod.Phys.A23:1891-1901,2008 | 10.1142/S0217751X08039773 | null | gr-qc math-ph math.MP | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The purely affine, metric-affine and purely metric formulation of general
relativity are dynamically equivalent and the relation between them is
analogous to the Legendre relation between the Lagrangian and Hamiltonian
dynamics. We show that one cannot construct a dynamically equivalent, purely
affine Lagrangian from a metric-affine or metric F(R) Lagrangian, nonlinear in
the curvature scalar. Thus the equivalence between the purely affine picture
and the two other formulations does not hold for metric-affine and metric
theories of gravity with a nonlinear dependence on the curvature, i.e. F(R)
gravity does not have a purely affine formulation. We also show that this
equivalence is restored if the metric tensor is conformally transformed from
the Jordan to the Einstein frame, in which F(R) gravity turns into general
relativity with a scalar field. This peculiar behavior of general relativity,
among relativistic theories of gravitation, with respect to purely affine,
metric-affine and purely metric variation could indicate the physicality of the
Einstein frame. On the other hand, it could explain why this theory cannot
interpolate among phenomenological behaviors at different scales.
| [
{
"version": "v1",
"created": "Fri, 29 Jun 2007 19:14:46 GMT"
},
{
"version": "v2",
"created": "Wed, 11 Jul 2007 06:10:27 GMT"
},
{
"version": "v3",
"created": "Fri, 4 Jul 2008 22:17:00 GMT"
}
] | 2014-11-18T00:00:00 | [
[
"Poplawski",
"Nikodem J.",
""
]
] |
0706.4475 | Liu Zhao | Liu Zhao | Black chain of pearls in 5D de Sitter spacetime | 4 pages, 3 figures. Wrong statements on stability based on error
incaculations corrected. New references added | null | null | null | hep-th | null | We analyze some exact chain-shaped black hole solutions in 5-dimensional
spacetime. Unlike usual black string and black ring solutions, the topology of
the horizons of the new solutions are neither $\mathbb{R}\times R^{2}$ nor
$S^1\times S^2$ but rather like several topological spheres concatenating each
other at single points. The shape of the horizon suggests the name \emph{black
chain of pearls} on which each \emph{pearl} is a topological 3-sphere on the
chain. In addition to the usual black hole hairs, the number of pearls can be
viewed as a new hair of the black chain of pearls.
| [
{
"version": "v1",
"created": "Fri, 29 Jun 2007 19:22:52 GMT"
},
{
"version": "v2",
"created": "Sun, 1 Jul 2007 18:07:43 GMT"
}
] | 2007-07-02T00:00:00 | [
[
"Zhao",
"Liu",
""
]
] |
0706.4476 | Anton Rebhan | Christoph Mayrhofer, Anton Rebhan, Peter van Nieuwenhuizen, Robert
Wimmer | Perturbative Quantum Corrections to the Supersymmetric CP^1 Kink with
Twisted Mass | 1+17 pages, 2 figures, JHEP style. v2: minor corrections, references
added. Dedicated to the memory of Wolfgang Kummer | JHEP 0709:069,2007 | 10.1088/1126-6708/2007/09/069 | YITP-SB-07-20 | hep-th | null | We present an explicit calculation of the one-loop quantum corrections to the
mass and the two central charges of the kink solution of an N=(2,2)
supersymmetric CP^1 model with twisted mass, using supersymmetry preserving
dimensional regularization adapted to solitons. We find that the quantum
corrections of the mass and one of the central charges are nontrivial (but
saturate the BPS bound), while the other central charge receives no
corrections. The nontrivial central charge correction corresponds to a quantum
anomaly, which in our scheme appears as parity violation in the regulating
extra dimension, and its magnitude is in agreement with exact results obtained
by Dorey on the basis of a massive analog of mirror symmetry from a dual U(1)
gauge theory, confirming also the recent work by Shifman, Vainshtein, and
Zwicky.
| [
{
"version": "v1",
"created": "Fri, 29 Jun 2007 19:39:09 GMT"
},
{
"version": "v2",
"created": "Mon, 13 Aug 2007 19:33:13 GMT"
}
] | 2009-04-30T00:00:00 | [
[
"Mayrhofer",
"Christoph",
""
],
[
"Rebhan",
"Anton",
""
],
[
"van Nieuwenhuizen",
"Peter",
""
],
[
"Wimmer",
"Robert",
""
]
] |
0706.4477 | Igor Nikolaev | Igor Nikolaev | On a Teichmueller functor between the categories of complex tori and the
Effros-Shen algebras | 8 pages; 2 figures; final version; to appear New York J. Math.
Available online at: http://nyjm.albany.edu/j/2009/15-6.html | New York J. Math. 15 (2009), 125-132 | null | null | math.AG math.OA | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | A covariant functor from the category of the complex tori to the category of
the Effros-Shen algebras is constructed. The functor maps isomorphic complex
tori to the stably isomorphic Effros-Shen algebras. Our construction is based
on the Teichmueller theory of the Riemann surfaces.
| [
{
"version": "v1",
"created": "Fri, 29 Jun 2007 19:37:09 GMT"
},
{
"version": "v2",
"created": "Tue, 7 Apr 2009 14:38:20 GMT"
}
] | 2009-05-01T00:00:00 | [
[
"Nikolaev",
"Igor",
""
]
] |
0706.4478 | Dave Bacon | Dave Bacon and Thomas Decker | The Optimal Single Copy Measurement for the Hidden Subgroup Problem | 8 pages. Error in main proof fixed | Physical Review A, 77, 032335 (2008) | 10.1103/PhysRevA.77.032335 | null | quant-ph | null | The optimization of measurements for the state distinction problem has
recently been applied to the theory of quantum algorithms with considerable
successes, including efficient new quantum algorithms for the non-abelian
hidden subgroup problem. Previous work has identified the optimal single copy
measurement for the hidden subgroup problem over abelian groups as well as for
the non-abelian problem in the setting where the subgroups are restricted to be
all conjugate to each other. Here we describe the optimal single copy
measurement for the hidden subgroup problem when all of the subgroups of the
group are given with equal a priori probability. The optimal measurement is
seen to be a hybrid of the two previously discovered single copy optimal
measurements for the hidden subgroup problem.
| [
{
"version": "v1",
"created": "Fri, 29 Jun 2007 19:43:40 GMT"
},
{
"version": "v2",
"created": "Tue, 22 Jan 2008 19:07:42 GMT"
}
] | 2008-03-26T00:00:00 | [
[
"Bacon",
"Dave",
""
],
[
"Decker",
"Thomas",
""
]
] |
0706.4479 | Simon Chelkowski | Simon Chelkowski, Henning Vahlbruch, Boris Hage, Alexander Franzen,
Nico Lastzka, Karsten Danzmann and Roman Schnabel | Experimental characterization of frequency dependent squeezed light | 8 pages, 8 figures | Physical Review A 71, 013806 (2005) | 10.1103/PhysRevA.71.013806 | null | quant-ph | null | We report on the demonstration of broadband squeezed laser beams that show a
frequency dependent orientation of the squeezing ellipse. Carrier frequency as
well as quadrature angle were stably locked to a reference laser beam at
1064nm. This frequency dependent squeezing was characterized in terms of noise
power spectra and contour plots of Wigner functions. The later were measured by
quantum state tomography. Our tomograph allowed a stable lock to a local
oscillator beam for arbitrary quadrature angles with one degree precision.
Frequency dependent orientations of the squeezing ellipse are necessary for
squeezed states of light to provide a broadband sensitivity improvement in
third generation gravitational wave interferometers. We consider the
application of our system to long baseline interferometers such as a future
squeezed light upgraded GEO600 detector.
| [
{
"version": "v1",
"created": "Fri, 29 Jun 2007 19:45:48 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Chelkowski",
"Simon",
""
],
[
"Vahlbruch",
"Henning",
""
],
[
"Hage",
"Boris",
""
],
[
"Franzen",
"Alexander",
""
],
[
"Lastzka",
"Nico",
""
],
[
"Danzmann",
"Karsten",
""
],
[
"Schnabel",
"Roman",
""
]
] |
0706.4480 | Daniel Silevitch | D. M. Silevitch, C. M. S. Gannarelli, A. J. Fisher, G. Aeppli, T. F.
Rosenbaum | Quantum Projection in an Ising Spin Liquid | 5 pages, 4 figures | Phys. Rev. Lett 99 057203 (2007) | 10.1103/PhysRevLett.99.057203 | null | cond-mat.other cond-mat.dis-nn | null | A transverse magnetic field is used to scan the diagonal and off-diagonal
susceptibility of the uniaxial quantum magnet,
$\text{LiHo}_{0.045}\text{Y}_{0.955}\text{F}_4$. Clusters of strongly-coupled
spins act as the primary source for the response functions, which result from a
field-induced quantum projection of the system into a classically forbidden
(meaning non-Ising) regime. Calculations based on spin pairs reproduce only
some features of the data and fail to predict the measured off-diagonal
response, providing evidence of a multi-spin collective state.
| [
{
"version": "v1",
"created": "Fri, 29 Jun 2007 19:54:24 GMT"
},
{
"version": "v2",
"created": "Thu, 2 Aug 2007 16:59:53 GMT"
}
] | 2007-08-02T00:00:00 | [
[
"Silevitch",
"D. M.",
""
],
[
"Gannarelli",
"C. M. S.",
""
],
[
"Fisher",
"A. J.",
""
],
[
"Aeppli",
"G.",
""
],
[
"Rosenbaum",
"T. F.",
""
]
] |
0706.4481 | Stephon Alexander | Stephon H.S. Alexander | Isogravity: Toward an Electroweak and Gravitational Unification | null | null | null | null | hep-th | null | We present a model that unites the electroweak interaction with general
relativity without specifying a space-time metric. This is made possible by
embedding the kinetic terms for gravity and electroweak theory using one $\SL$
connection variable. The gauge theory is specified without relying on a
space-time metric. We show that once a symmetry breaking mechanism is
implemented that selects a global time-like direction, the electroweak theory
and general relativity emerges with their associated massless degrees of
freedom; the spin 1 vector boson and the spin 2 graviton.
| [
{
"version": "v1",
"created": "Fri, 29 Jun 2007 19:58:42 GMT"
}
] | 2007-07-02T00:00:00 | [
[
"Alexander",
"Stephon H. S.",
""
]
] |
0706.4482 | James P. Zibin | J. P. Zibin, A. Moss, D. Scott | The Evolution of the Cosmic Microwave Background | 23 pages, 11 figures; references added; one figure dropped and minor
changes to match published version. For high-resolution versions of figures
and animations, see http://www.astro.ubc.ca/people/scott/future.html | Phys.Rev.D76:123010,2007 | 10.1103/PhysRevD.76.123010 | null | astro-ph | null | We discuss the time dependence and future of the Cosmic Microwave Background
(CMB) in the context of the standard cosmological model, in which we are now
entering a state of endless accelerated expansion. The mean temperature will
simply decrease until it reaches the effective temperature of the de Sitter
vacuum, while the dipole will oscillate as the Sun orbits the Galaxy. However,
the higher CMB multipoles have a richer phenomenology. The CMB anisotropy power
spectrum will for the most part simply project to smaller scales, as the
comoving distance to last scattering increases, and we derive a scaling
relation that describes this behaviour. However, there will also be a dramatic
increase in the integrated Sachs-Wolfe contribution at low multipoles. We also
discuss the effects of tensor modes and optical depth due to Thomson
scattering. We introduce a correlation function relating the sky maps at two
times and the closely related power spectrum of the difference map. We compute
the evolution both analytically and numerically, and present simulated future
sky maps.
| [
{
"version": "v1",
"created": "Fri, 29 Jun 2007 19:56:00 GMT"
},
{
"version": "v2",
"created": "Tue, 3 Jul 2007 19:55:19 GMT"
},
{
"version": "v3",
"created": "Thu, 20 Dec 2007 00:32:12 GMT"
}
] | 2008-11-26T00:00:00 | [
[
"Zibin",
"J. P.",
""
],
[
"Moss",
"A.",
""
],
[
"Scott",
"D.",
""
]
] |
0706.4483 | Omer Blaes | Omer M. Blaes, Eva Sramkova, Marek A. Abramowicz, Wlodek Kluzniak and
Ulf Torkelsson | Epicyclic Oscillations of Fluid Bodies: Newtonian Nonslender Torus | ApJ, in press | Astrophys.J.665:642-653,2007 | 10.1086/519782 | null | astro-ph | null | We study epicyclic oscillations of fluid tori around black holes (in the
Paczynski-Wiita potential) and derive exact analytic expressions for their
radial and vertical eigenfrequencies nu_r and nu_z to second-order accuracy in
the width of the torus. We prove that pressure effects make the
eigenfrequencies smaller than those for free particles. However, the particular
ratio nu_z/nu_r=3/2, which is important for the theory of high-frequency
quasi-periodic oscillations (QPOs), occurs when the fluid tori epicyclic
frequencies nu_r and nu_z are about 15% higher than the ones corresponding to
free particles. Our results therefore suggest that previous estimates of black
hole spins from QPOs have produced values that are too high.
| [
{
"version": "v1",
"created": "Fri, 29 Jun 2007 19:57:32 GMT"
}
] | 2011-02-11T00:00:00 | [
[
"Blaes",
"Omer M.",
""
],
[
"Sramkova",
"Eva",
""
],
[
"Abramowicz",
"Marek A.",
""
],
[
"Kluzniak",
"Wlodek",
""
],
[
"Torkelsson",
"Ulf",
""
]
] |
0706.4484 | Ching-Wa Yip | Ching-Wa Yip (JHU) | Spectroscopic Surveys: Present | 9 pages, 1 figure, 2 tables. Invited talk given at the Astronomical
Spectroscopy and The Virtual Observatory WorkShop 2007 | null | null | null | astro-ph | null | I summarize the current spectroscopic sky surveys and some of the scientific
results, emphasizing the largest sky survey to-date, the Sloan Digital Sky
Survey (SDSS). Techniques used commonly in spectral analyses are discussed,
followed by the present needs and challenges for solving some of the unknown
problems. I discuss how the Virtual Observatory (VO) can help astronomers in
carrying out related research.
| [
{
"version": "v1",
"created": "Fri, 29 Jun 2007 19:59:36 GMT"
},
{
"version": "v2",
"created": "Fri, 29 Jun 2007 21:52:07 GMT"
}
] | 2007-07-02T00:00:00 | [
[
"Yip",
"Ching-Wa",
"",
"JHU"
]
] |
0707.0001 | Pavel Krtous | Pavel Krtous, David Kubiznak, Don N. Page, Muraari Vasudevan | Constants of Geodesic Motion in Higher-Dimensional Black-Hole Spacetimes | 8 pages, no figures | Phys.Rev.D76:084034,2007 | 10.1103/PhysRevD.76.084034 | Alberta-Thy-05-07 | hep-th gr-qc | null | In [arXiv:hep-th/0611083] we announced the complete integrability of geodesic
motion in the general higher-dimensional rotating black-hole spacetimes. In the
present paper we prove all the necessary steps leading to this conclusion. In
particular, we demonstrate the independence of the constants of motion and the
fact that they Poisson commute. The relation to a different set of constants of
motion constructed in [arXiv:hep-th/0612029] is also briefly discussed.
| [
{
"version": "v1",
"created": "Fri, 29 Jun 2007 20:00:13 GMT"
}
] | 2008-11-26T00:00:00 | [
[
"Krtous",
"Pavel",
""
],
[
"Kubiznak",
"David",
""
],
[
"Page",
"Don N.",
""
],
[
"Vasudevan",
"Muraari",
""
]
] |
0707.0002 | Pavel Krtous | Pavel Krtous | Electromagnetic Field in Higher-Dimensional Black-Hole Spacetimes | 8 pages, no figures; presented at the Black hole VI conference in
White Point, Canada, May 12-16 2007, and at the GRG18 conference in Sydney,
Australia, July 8-13 2007 | Phys.Rev.D76:084035,2007 | 10.1103/PhysRevD.76.084035 | null | hep-th gr-qc | null | A special test electromagnetic field in the spacetime of the
higher-dimensional generally rotating NUT-(A)dS black hole is found. It is
adjusted to the hidden symmetries of the background represented by the
principal Killing-Yano tensor. Such electromagnetic field generalizes the field
of charged black hole in four dimensions. In higher dimensions, however, the
gravitational back reaction of such a field cannot be consistently solved.
| [
{
"version": "v1",
"created": "Sun, 1 Jul 2007 22:34:41 GMT"
}
] | 2008-11-26T00:00:00 | [
[
"Krtous",
"Pavel",
""
]
] |
0707.0003 | Shawn Poindexter | Shawn Poindexter, Nicholas Morgan, Christopher S. Kochanek (Department
of Astronomy, The Ohio State University) | The Spatial Structure of An Accretion Disk | 5 pages, 4 figures, submitted to ApJ | null | 10.1086/524190 | null | astro-ph | null | Based on the microlensing variability of the two-image gravitational lens
HE1104-1805 observed between 0.4 and 8 microns, we have measured the size and
wavelength-dependent structure of the quasar accretion disk. Modeled as a power
law in temperature, T proportional to R^-beta, we measure a B-band (0.13
microns in the rest frame) half-light radius of R_{1/2,B} = 6.7 (+6.2 -3.2) x
10^15 cm (68% CL) and a logarithmic slope of beta=0.61 (+0.21 -0.17) for our
standard model with a logarithmic prior on the disk size. Both the scale and
the slope are consistent with simple thin disk models where beta=3/4 and
R_{1/2,B} = 5.9 x 10^15 cm for a Shakura-Sunyaev disk radiating at the
Eddington limit with 10% efficiency. The observed fluxes favor a slightly
shallower slope, beta=0.55 (+0.03 -0.02), and a significantly smaller size for
beta=3/4.
| [
{
"version": "v1",
"created": "Fri, 29 Jun 2007 20:01:19 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Poindexter",
"Shawn",
"",
"Department\n of Astronomy, The Ohio State University"
],
[
"Morgan",
"Nicholas",
"",
"Department\n of Astronomy, The Ohio State University"
],
[
"Kochanek",
"Christopher S.",
"",
"Department\n of Astronomy, The Ohio State University"
]
] |
0707.0004 | Yasuhide Numata | Yasuhide Numata | An Algorithm to Construct A Basis for the Module of Logarithmic Vector
Fields | null | null | null | null | math.CO | null | We consider logarithmic vector fields parametrized by finite collections of
weighted hyperplanes. For a finite collection of weighted hyperplanes in a
two-dimensional vector space, it is known that the set of such vector fields is
a free module of rank two whose basis elements are homogeneous. We give an
algorithm to construct a homogeneous basis for the module.
| [
{
"version": "v1",
"created": "Fri, 29 Jun 2007 20:07:51 GMT"
}
] | 2007-07-03T00:00:00 | [
[
"Numata",
"Yasuhide",
""
]
] |
0707.0005 | Scott Thomas | Michael Dine, Nathan Seiberg and Scott Thomas | Higgs Physics as a Window Beyond the MSSM (BMSSM) | LaTex, 28 pages | Phys.Rev.D76:095004,2007 | 10.1103/PhysRevD.76.095004 | SCIPP 07/13, RU-NHETC-07-10 | hep-ph | null | We interpret the current experimental limit on the lightest Higgs boson mass
to suggest that if nature is supersymmetric, there are additional interactions
beyond those of the MSSM coming from new degrees of freedom around the TeV
scale. Within an effective field theory analysis, the leading order corrections
to the MSSM are described in terms of only two operators. This provides a
highly constrained description of Beyond MSSM (BMSSM) physics. The scalar Higgs
spectrum as well as the chargino and neutralino spectrum and couplings are
modified in a distinctive way. These operators can be generated by a variety of
microscopic mechanisms.
| [
{
"version": "v1",
"created": "Fri, 29 Jun 2007 20:08:08 GMT"
},
{
"version": "v2",
"created": "Tue, 10 Jul 2007 19:49:25 GMT"
},
{
"version": "v3",
"created": "Tue, 7 Aug 2007 20:09:48 GMT"
}
] | 2008-11-26T00:00:00 | [
[
"Dine",
"Michael",
""
],
[
"Seiberg",
"Nathan",
""
],
[
"Thomas",
"Scott",
""
]
] |
0707.0006 | Toru Misawa | T. Misawa, D. Tytler, M. Iye, D. Kirkman, N. Suzuki, D. Lubin, N.
Kashikawa | Spectroscopic Analysis of H I Absorption Line Systems in 40 HIRES
Quasars | 32 pages, 14 figures, accepted for publication in the Astronomical
Journal. A complete version with all tables and figures is available at
http://www.astro.psu.edu/users/misawa/pub/Paper/40hires.ps.gz | Astron.J.134:1634-1654,2007 | 10.1086/521557 | null | astro-ph | null | We list and analyze H I absorption lines at redshifts 2 < z < 4 with column
density (12 < log(N_HI) < 19) in 40 high-resolutional (FWHM = 8.0 km/s) quasar
spectra obtained with the Keck+HIRES. We de-blend and fit all H I lines within
1,000 km/s of 86 strong H I lines whose column densities are log(N_HI/[cm^-2])
> 15. Unlike most prior studies, we use not only Lya but also all visible
higher Lyman series lines to improve the fitting accuracy. This reveals
components near to higher column density systems that can not be seen in Lya.
We list the Voigt profile fits to the 1339 H I components that we found. We
examined physical properties of H I lines after separating them into several
sub-samples according to their velocity separation from the quasars, their
redshift, column density and the S/N ratio of the spectrum. We found two
interesting trends for lines with 12 < log(N_HI) < 15 which are within 200-1000
km/s of systems with log(N_HI) > 15. First, their column density distribution
becomes steeper, meaning relatively fewer high column density lines, at z <
2.9. Second, their column density distribution also becomes steeper and their
line width becomes broader by about 2-3 km/s when they are within 5,000 km/s of
their quasar.
| [
{
"version": "v1",
"created": "Fri, 29 Jun 2007 20:08:09 GMT"
}
] | 2008-11-26T00:00:00 | [
[
"Misawa",
"T.",
""
],
[
"Tytler",
"D.",
""
],
[
"Iye",
"M.",
""
],
[
"Kirkman",
"D.",
""
],
[
"Suzuki",
"N.",
""
],
[
"Lubin",
"D.",
""
],
[
"Kashikawa",
"N.",
""
]
] |
0707.0007 | Gonzalo Torroba MsC | Rouven Essig, Kuver Sinha, Gonzalo Torroba | Meta-Stable Dynamical Supersymmetry Breaking Near Points of Enhanced
Symmetry | 27 pages, harvmac, 6 figures | JHEP 0709:032,2007 | 10.1088/1126-6708/2007/09/032 | RUNHETC-07-08 | hep-th hep-ph | null | We show that metastable supersymmetry breaking is generic near certain
enhanced symmetry points of gauge theory moduli spaces. Our model consists of
two sectors coupled by a singlet and combines dynamical supersymmetry breaking
with an O'Raifeartaigh mechanism in terms of confined variables. All relevant
mass parameters, including the supersymmetry breaking scale, are generated
dynamically. The metastable vacua appear as a result of a balance between
non-perturbative and perturbative quantum effects along a pseudo-runaway
direction.
| [
{
"version": "v1",
"created": "Mon, 2 Jul 2007 15:33:08 GMT"
}
] | 2009-04-30T00:00:00 | [
[
"Essig",
"Rouven",
""
],
[
"Sinha",
"Kuver",
""
],
[
"Torroba",
"Gonzalo",
""
]
] |
0707.0008 | Gerald Gilbert | Gerald Gilbert, Michael Hamrick, Yaakov S. Weinstein | Reliable Final Computational Results from Faulty Quantum Computation | 7 pages, 2 figures | null | null | null | quant-ph | null | In this paper we extend both standard fault tolerance theory and Kitaev's
model for quantum computation, combining them so as to yield quantitative
results that reveal the interplay between the two. Our analysis establishes a
methodology that allows us to quantitatively determine design parameters for a
quantum computer, the values of which ensure that an overall computation of
interest yields a correct *final result* with some prescribed probability of
success, as opposed to merely ensuring that the desired *final quantum state*
is obtained. As a specific example of the practical application of our
approach, we explicitly calculate the number of levels of error correction
concatenation needed to achieve a correct final result for the overall
computation with some prescribed success probability. Since our methodology
allows one to determine parameters required in order to achieve the correct
final result for the overall quantum computation, as opposed to merely ensuring
that the desired final quantum state is produced, our method enables the
determination of complete quantum computational resource requirements
associated to the actual solution of practical problems.
| [
{
"version": "v1",
"created": "Fri, 29 Jun 2007 20:20:21 GMT"
}
] | 2007-07-03T00:00:00 | [
[
"Gilbert",
"Gerald",
""
],
[
"Hamrick",
"Michael",
""
],
[
"Weinstein",
"Yaakov S.",
""
]
] |
0707.0009 | Julia Kuznetsova | Yulia N. Kuznetsova | Invariant weighted algebras $L_p^w(G)$ | Submitted to Mat. Zametki. 12 pages | Mat. Zametki 84, no. 4, pp. 567-576 (2008) | null | null | math.FA | null | The paper deals with weighted spaces $L_p^w(G)$ on a locally compact group G.
If w is a positive measurable function on G then we define the space
$L_p^w(G)$, $p\ge1$, as $L_p^w(G)=\{f:fw\in L_p(G)\}$. We consider weights such
that these weighted spaces are algebras with respect to usual convolution. It
is shown that for p>1 such weights exists on any sigma-compact group. We prove
also a criterion known earlier in special cases: $L_1^w(G)$ is an algebra if
and only if w is submultiplicative. It is proved that invariant algebras
$L_p^w(G)$, $p>1$, have approximate units of standard form, but this may not be
true for a non-invariant algebra.
| [
{
"version": "v1",
"created": "Mon, 2 Jul 2007 13:15:22 GMT"
},
{
"version": "v2",
"created": "Sat, 5 Apr 2008 07:47:36 GMT"
}
] | 2012-06-28T00:00:00 | [
[
"Kuznetsova",
"Yulia N.",
""
]
] |
0707.0010 | Jean-Christophe Pain | J.C. Pain | Equation-of-state model for shock compression of hot dense matter | null | Physics Letters A 362, 120-124 (2007) | 10.1016/j.physleta.2006.10.013 | null | physics.plasm-ph | null | A quantum equation-of-state model is presented and applied to the calculation
of high-pressure shock Hugoniot curves beyond the asymptotic fourfold density,
close to the maximum compression where quantum effects play a role. An
analytical estimate for the maximum attainable compression is proposed. It
gives a good agreement with the equation-of-state model.
| [
{
"version": "v1",
"created": "Fri, 29 Jun 2007 20:29:02 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Pain",
"J. C.",
""
]
] |
0707.0011 | Marko Horvat B.Sc.CS-Dipl.Ing. | Marko Horvat | Calculating the probability of detecting radio signals from alien
civilizations | 10 pages, 1 figure, 2 tables; corrected typos and missing references | M. Horvat, International Journal of Astrobiology, 5, 143-149
(2006) | 10.1017/S1473550406003004 | null | physics.pop-ph astro-ph | null | Although it might not be self-evident, it is in fact entirely possible to
calculate the probability of detecting alien radio signals by understanding
what types of extraterrestrial radio emissions can be expected and what
properties these emissions can have. Using the Drake equation as the obvious
starting point, and logically identifying and enumerating constraints of
interstellar radio communications can yield the probability of detecting a
genuine alien radio signal.
| [
{
"version": "v1",
"created": "Fri, 29 Jun 2007 20:25:44 GMT"
},
{
"version": "v2",
"created": "Sat, 14 Jul 2007 00:08:05 GMT"
}
] | 2011-11-10T00:00:00 | [
[
"Horvat",
"Marko",
""
]
] |
0707.0012 | Shivakumar Jolad | Shivakumar Jolad, Chia-Chen Chang, Jainendra K. Jain | Electron operator at the edge of the 1/3 fractional quantum Hall liquid | 10 pages, 2 figures | Phys. Rev. B 75, 165306 (2007) | 10.1103/PhysRevB.75.165306 | null | cond-mat.mes-hall | null | This study builds upon the work of Palacios and MacDonald (Phys. Rev. Lett.
{\bf 76}, 118 (1996)), wherein they identify the bosonic excitations of Wen's
approach for the edge of the 1/3 fractional quantum Hall state with certain
operators introduced by Stone. Using a quantum Monte Carlo method, we extend to
larger systems containing up to 40 electrons and obtain more accurate
thermodynamic limits for various matrix elements for a short range interaction.
The results are in agreement with those of Palacios and MacDonald for small
systems, but offer further insight into the detailed approach to the
thermodynamic limit. For the short range interaction, the results are
consistent with the chiral Luttinger liquid predictions.We also study
excitations using the Coulomb ground state for up to nine electrons to
ascertain the effect of interactions on the results; in this case our tests of
the chiral Luttinger liquid approach are inconclusive.
| [
{
"version": "v1",
"created": "Fri, 29 Jun 2007 20:50:35 GMT"
}
] | 2007-07-03T00:00:00 | [
[
"Jolad",
"Shivakumar",
""
],
[
"Chang",
"Chia-Chen",
""
],
[
"Jain",
"Jainendra K.",
""
]
] |
0707.0013 | Jean-Christophe Pain | J.C. Pain | Shell-structure effects on high-pressure Rankine-Hugoniot shock adiabats | null | High Energy Density Phys. 3, 204-210 (2007) | 10.1016/j.hedp.2007.02.013 | null | physics.plasm-ph physics.atom-ph | null | Rankine-Hugoniot shock adiabats are calculated in the pressure range 1
Mbar-10 Gbar with two atomic-structure models: the atom in a spherical cell and
the atom in a jellium of charges. These quantum self-consistent-field models
include shell effects, which have a strong impact on pressure and shock
velocity along the shock adiabat. Comparisons with experimental data are
presented and quantum effects are interpreted in terms of electronic specific
heat. A simple analytical estimate for the maximum compression is proposed,
depending on initial density, atomic weight and atomic number.
| [
{
"version": "v1",
"created": "Fri, 29 Jun 2007 20:40:04 GMT"
}
] | 2015-05-13T00:00:00 | [
[
"Pain",
"J. C.",
""
]
] |
0707.0014 | Maxim Perelstein | Csaba Csaki, Johannes Heinonen and Maxim Perelstein | Testing Gluino Spin with Three-Body Decays | 19 pages, 10 figures | JHEP 0710:107,2007 | 10.1088/1126-6708/2007/10/107 | null | hep-ph | null | We examine the possibility of distinguishing a supersymmetric gluino from a
Kaluza-Klein gluon of universal extra dimensions (UED) at the Large Hadron
Collider (LHC). We focus on the case when all kinematically allowed tree-level
decays of this particle are 3-body decays into two jets and a massive daughter
(typically weak gaugino or Kaluza-Klein weak gauge boson). We show that the
shapes of the dijet invariant mass distributions differ significantly in the
two models, as long as the mass of the decaying particle mA is substantially
larger than the mass of the massive daughter mB. We present a simple analysis
estimating the number of events needed to distinguish between the two models
under idealized conditions. For example, for mA/mB=10, we find the required
number of events to be of order several thousand, which should be available at
the LHC within a few years. This conclusion is confirmed by a parton level
Monte Carlo study which includes the effects of experimental cuts and the
combinatoric background.
| [
{
"version": "v1",
"created": "Fri, 29 Jun 2007 21:05:13 GMT"
}
] | 2009-09-17T00:00:00 | [
[
"Csaki",
"Csaba",
""
],
[
"Heinonen",
"Johannes",
""
],
[
"Perelstein",
"Maxim",
""
]
] |
0707.0015 | G\'abor Zsolt T\'oth | Gabor Zsolt Toth (Hungarian Acad. Sci., Budapest) | Investigations in Two-Dimensional Quantum Field Theory by the Bootstrap
and TCSA Methods | PhD thesis, 195 pages, v2: minor correction in section 3.4.1 | null | null | null | hep-th | null | This thesis contains three main parts, which are largely independent. In the
first part we deal with the boundary bootstrap in supersymmetric factorized
scattering theory. We give a description of supersymmetry in the case when the
space is a half-line and present rules for the determination of the
representations in which higher level boundary bound states transform, and for
the determination of the supersymmetric one-particle reflection matrix factors
for the higher level boundary bound states. These rules apply under the
condition that the bulk particles transform in the kink or in the boson-fermion
representation. Examples for the application of these rules to specific models
are also given. In the second part we investigate the problem whether the TCSA
spectrum can be approximated by the spectrum of the original Hamiltonian
operator in which the coefficients of the terms are suitably changed. The
investigation is done in the case of the critical Ising model on a strip with
an external magnetic field on one of the boundaries. Another truncation method
that preserves the solvability of the model is also considered. The results of
perturbative and numerical calculations show that the above approximation is
possible and that the qualitative behaviour of the truncated spectrum as a
function of the coupling constant depends on the truncation method. In the
third part we investigate the phase structure of the two- and three-frequency
sine-Gordon models using the TCSA. In the case of the three-frequency model the
tricritical point, several points of the critical line and a few points of the
line of first order transition are found.
| [
{
"version": "v1",
"created": "Sat, 30 Jun 2007 19:26:57 GMT"
},
{
"version": "v2",
"created": "Wed, 21 Nov 2007 18:08:53 GMT"
}
] | 2007-11-21T00:00:00 | [
[
"Toth",
"Gabor Zsolt",
"",
"Hungarian Acad. Sci., Budapest"
]
] |
0707.0016 | Aldo Procacci | Aldo Procacci | Abstract polymer models with general pair interactions | 19 pages. Corrected statement for the stability condition (2.3) and
modified section 3.1 of the proof of theorem 1 consistently with (2.3). Added
a reference and modified a sentence at the end of sec. 2.1 | Journal of Statistical Physics 129, n.1 171-188 (2007) | 10.1007/s10955-007-9378-x | null | math-ph math.CO math.MP | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | A convergence criterion of cluster expansion is presented in the case of an
abstract polymer system with general pair interactions (i.e. not necessarily
hard core or repulsive). As a concrete example, the low temperature disordered
phase of the BEG model with infinite range interactions, decaying polynomially
as $1/r^{d+\lambda}$ with $\lambda>0$, is studied.
| [
{
"version": "v1",
"created": "Fri, 29 Jun 2007 21:21:22 GMT"
},
{
"version": "v2",
"created": "Wed, 26 Nov 2008 02:33:10 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Procacci",
"Aldo",
""
]
] |
0707.0017 | Hannes Junginger-Gestrich | Hannes Junginger-Gestrich | A Morse type uniqueness theorem for non-parametric minimizing
hypersurfaces | 17 pages, 1 figure | null | null | null | math.AP math.DS | null | A classical result about minimal geodesics on R^2 with Z^2 periodic metric
that goes back to H.M. Morse asserts that a minimal geodesic that is asymptotic
to a periodic minimal geodesic cannot intersect any periodic minimal geodesic
of the same period. This paper treats a similar theorem for nonparametric
minimizing hypersurfaces without selfintersections -- as were studied by J.
Moser, V. Bangert, P.H. Rabinowitz, E. Stredulinsky and others.
| [
{
"version": "v1",
"created": "Mon, 2 Jul 2007 06:34:46 GMT"
}
] | 2007-07-03T00:00:00 | [
[
"Junginger-Gestrich",
"Hannes",
""
]
] |
0707.0018 | Seung-Ho Baek | S.-H. Baek, K.-Y. Choi, A. P. Reyes, P. L. Kuhns, N. J. Curro, V.
Ramanchandran, N. S. Dalal, H. D. Zhou, and C. R. Wiebe | AC susceptibility and $^{51}$V NMR study of MnV$_2$O$_4$ | null | J. Phys. Condens. Matter, 20, 135218 (2008) | 10.1088/0953-8984/20/13/135218 | null | cond-mat.str-el | null | We report $^{51}$V zero-field NMR of manganese vanadate spinel of
MnV$_2$O$_4$, together with both ac and dc magnetization measurements. The
field and temperature dependence of ac susceptibilities show a
reentrant-spin-glass-like behavior below the ferrimagnetic(FEM) ordering
temperature. The zero-field NMR spectrum consists of multiple lines ranging
from 240 MHz to 320 MHz. Its temperature dependence reveals that the ground
state is given by the simultaneous formation of a long-range FEM order and a
short-range order component. We attribute the spin-glass-like anomalies to
freezing and fluctuations of the short-range ordered state caused by the
competition between spin and orbital ordering of the V site.
| [
{
"version": "v1",
"created": "Fri, 29 Jun 2007 21:26:47 GMT"
}
] | 2015-05-13T00:00:00 | [
[
"Baek",
"S. -H.",
""
],
[
"Choi",
"K. -Y.",
""
],
[
"Reyes",
"A. P.",
""
],
[
"Kuhns",
"P. L.",
""
],
[
"Curro",
"N. J.",
""
],
[
"Ramanchandran",
"V.",
""
],
[
"Dalal",
"N. S.",
""
],
[
"Zhou",
"H. D.",
""
],
[
"Wiebe",
"C. R.",
""
]
] |
0707.0019 | Catherine Espaillat | Catherine Espaillat, Nuria Calvet, Paola D'Alessio, Edwin Bergin, Lee
Hartmann, Dan Watson, Elise Furlan, Joan Najita, William Forrest, Melissa
McClure, Ben Sargent, Chris Bohac, Samuel T. Harrold | Probing the Dust and Gas in the Transitional Disk of CS Cha with Spitzer | accepted to ApJ Letters | null | 10.1086/520879 | null | astro-ph | null | Here we present the Spitzer IRS spectrum of CS Cha, a member of the ~2 Myr
old Chamaeleon star-forming region, which reveals an optically thick
circumstellar disk truncated at ~43 AU, the largest hole modeled in a
transitional disk to date. Within this inner hole, ~5x10^-5 lunar masses of
dust are located in a small optically thin inner region which extends from 0.1
to 1 AU. In addition, the disk of CS Cha has bigger grain sizes and more
settling than the previously modeled transitional disks DM Tau, GM Aur, and
CoKu Tau/4, suggesting that CS Cha is in a more advanced state of dust
evolution. The Spitzer IRS spectrum also shows [Ne II] 12.81 micron
fine-structure emission with a luminosity of 1.3x10^29 ergs s^-1, indicating
that optically thin gas is present in this ~43 AU hole, in agreement with
H_alpha measurements and a UV excess which indicate that CS Cha is still
accreting 1.2x10^-8 M_sun yr^-1. We do not find a correlation of the [Ne II]
flux with L_X, however, there is a possible correlation with mass accretion
rate, which if confirmed would suggest that EUV fluxes due to accretion are the
main agent for formation of the [Ne II] line.
| [
{
"version": "v1",
"created": "Fri, 29 Jun 2007 21:30:07 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Espaillat",
"Catherine",
""
],
[
"Calvet",
"Nuria",
""
],
[
"D'Alessio",
"Paola",
""
],
[
"Bergin",
"Edwin",
""
],
[
"Hartmann",
"Lee",
""
],
[
"Watson",
"Dan",
""
],
[
"Furlan",
"Elise",
""
],
[
"Najita",
"Joan",
""
],
[
"Forrest",
"William",
""
],
[
"McClure",
"Melissa",
""
],
[
"Sargent",
"Ben",
""
],
[
"Bohac",
"Chris",
""
],
[
"Harrold",
"Samuel T.",
""
]
] |
0707.0020 | Sogee Spinner | R. N. Mohapatra, N. Setzer and S. Spinner | Minimal Seesaw as an Ultraviolet Insensitive Cure for the Problems of
Anomaly Mediation | 19 pages, 1 figure | Phys.Rev.D77:053013,2008 | 10.1103/PhysRevD.77.053013 | null | hep-ph hep-th | null | We show that an intermediate scale supersymmetric left-right seesaw scenario
with automatic R-parity conservation can cure the problem of tachyonic slepton
masses that arises when supersymmetry is broken by anomaly mediation, while
preserving ultraviolet insensitivity. The reason for this is the existence of
light B - L = 2 higgses with yukawa couplings to the charged leptons. We find
these theories to have distinct predictions compared to the usual mSUGRA and
gauge mediated models as well as the minimal AMSB models. Such predictions
include a condensed gaugino mass spectrum and possibly a correspondingly
condensed sfermion spectrum.
| [
{
"version": "v1",
"created": "Mon, 2 Jul 2007 16:58:12 GMT"
}
] | 2008-11-26T00:00:00 | [
[
"Mohapatra",
"R. N.",
""
],
[
"Setzer",
"N.",
""
],
[
"Spinner",
"S.",
""
]
] |
0707.0021 | Daniel A. Lidar | Daniel A. Lidar (USC) | Towards Fault Tolerant Adiabatic Quantum Computation | Replaced with published version | Phys. Rev. Lett. 100, 160506 (2008) | 10.1103/PhysRevLett.100.160506 | null | quant-ph | null | I show how to protect adiabatic quantum computation (AQC) against decoherence
and certain control errors, using a hybrid methodology involving dynamical
decoupling, subsystem and stabilizer codes, and energy gaps. Corresponding
error bounds are derived. As an example I show how to perform
decoherence-protected AQC against local noise using at most two-body
interactions.
| [
{
"version": "v1",
"created": "Mon, 2 Jul 2007 16:17:11 GMT"
},
{
"version": "v2",
"created": "Mon, 5 Nov 2007 20:03:19 GMT"
},
{
"version": "v3",
"created": "Fri, 2 May 2008 05:09:32 GMT"
}
] | 2008-05-02T00:00:00 | [
[
"Lidar",
"Daniel A.",
"",
"USC"
]
] |
0707.0022 | Melvin Leok | Taeyoung Lee, Melvin Leok, N. Harris McClamroch | Lagrangian Mechanics and Variational Integrators on Two-Spheres | 19 pages, 7 figures | null | null | null | math.NA | null | Euler-Lagrange equations and variational integrators are developed for
Lagrangian mechanical systems evolving on a product of two-spheres. The
geometric structure of a product of two-spheres is carefully considered in
order to obtain global equations of motion. Both continuous equations of motion
and variational integrators completely avoid the singularities and complexities
introduced by local parameterizations or explicit constraints. We derive global
expressions for the Euler-Lagrange equations on two-spheres which are more
compact than existing equations written in terms of angles. Since the
variational integrators are derived from Hamilton's principle, they preserve
the geometric features of the dynamics such as symplecticity, momentum maps, or
total energy, as well as the structure of the configuration manifold.
Computational properties of the variational integrators are illustrated for
several mechanical systems.
| [
{
"version": "v1",
"created": "Sat, 30 Jun 2007 01:16:34 GMT"
}
] | 2007-07-03T00:00:00 | [
[
"Lee",
"Taeyoung",
""
],
[
"Leok",
"Melvin",
""
],
[
"McClamroch",
"N. Harris",
""
]
] |
0707.0023 | Herry J. Kwee | Herry J. Kwee | pi N to Multi-pi N Scattering in the 1/N_c Expansion | Invited talk at Exclusive Reactions at High Momentum Transfer
workshop, JLAB, Newport News, VA, May 21-24, 2007, 4 pages, 3 figures | null | 10.1142/9789812796950_0045 | null | hep-ph | null | We extend the 1/N_c meson-baryon scattering formalism to pi N to multi-pi N
case. We first show that the leading-order large N_c processes proceed through
resonant intermediate states (e.g., rho N or pi Delta). We find that the pole
structure of baryon resonances can be uniquely identified by their
(non)appearance in eta N or mixed partial-wave pi Delta final states.
| [
{
"version": "v1",
"created": "Fri, 29 Jun 2007 22:41:06 GMT"
}
] | 2017-08-23T00:00:00 | [
[
"Kwee",
"Herry J.",
""
]
] |
0707.0024 | Wayne Waldron Dr | Wayne L. Waldron and Joseph P. Cassinelli | An Extensive Collection of Stellar Wind X-ray Source Region Emission
Line Parameters,Temperatures, Velocities, and Their Radial Distributions as
Obtained from Chandra Observations of 17 OB Stars | Published in 2007, ApJ, 668, 456. An Erratum scheduled for
publication in 2008, ApJ, 680, is included as an Appendix. The Erratum
corrects some tabulated data in 5 tables and 2 figures | null | 10.1086/520919 | null | astro-ph | null | Chandra high energy resolution observations have now been obtained from
numerous non-peculiar O and early B stars. The observed X-ray emission line
properties differ from pre-launch predictions, and the interpretations are
still problematic. We present a straightforward analysis of a broad collection
of OB stellar line profile data to search for morphological trends. X-ray line
emission parameters and the spatial distributions of derived quantities are
examined with respect to luminosity class. The X-ray source locations and their
corresponding temperatures are extracted by using the He-like f/i line ratios
and the H-like to He-like line ratios respectively. Our luminosity class study
reveals line widths increasing with luminosity. Although the majority of the OB
emission lines are found to be symmetric, with little central line
displacement, there is evidence for small, but finite, blue-ward line-shifts
that also increase with luminosity. The spatial X-ray temperature distributions
indicate that the highest temperatures occur near the star and steadily
decrease outward. This trend is most pronounced in the OB supergiants. For the
lower density wind stars, both high and low X-ray source temperatures exist
near the star. However, we find no evidence of any high temperature X-ray
emission in the outer wind regions for any OB star. Since the temperature
distributions are counter to basic shock model predictions, we call this the
"near-star high-ion problem" for OB stars. By invoking the traditional OB
stellar mass loss rates, we find a good correlation between the fir-inferred
radii and their associated X-ray continuum optical depth unity radii. We
conclude by presenting some possible explanations to the X-ray source problems
that have been revealed by this study.
| [
{
"version": "v1",
"created": "Fri, 29 Jun 2007 22:59:30 GMT"
},
{
"version": "v2",
"created": "Mon, 17 Mar 2008 22:09:06 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Waldron",
"Wayne L.",
""
],
[
"Cassinelli",
"Joseph P.",
""
]
] |
0707.0025 | Tsuguo Mogami | Tsuguo Mogami | On quantization of massive non-Abelian gauge fields | 12 pages, 2 figures; added a reference | null | null | null | hep-ph | null | A simpler method of quantization is given for massive gauge theories. This
method gives the same results as those of the conventional massive gauge theory
with ghost and Higgs fields under the Higgs mass. Besides, we point out
physical importance of helicity zero states in non-Abelian gauge theories even
in massless case. Furthermore, forms of mass terms that were impossible before,
e.g. symmetric mass, are possible now. Applying our method to SU(2)xU(1)
symmetry has no particular difficulty, and gives a variant of the standard
model without the Higgs boson.
| [
{
"version": "v1",
"created": "Fri, 29 Jun 2007 23:59:56 GMT"
},
{
"version": "v2",
"created": "Tue, 16 Oct 2007 23:59:50 GMT"
}
] | 2007-10-17T00:00:00 | [
[
"Mogami",
"Tsuguo",
""
]
] |
0707.0026 | Maria A. Avi\~no-Diaz | Maria A. Avino-Diaz | Introducing a Probabilistic Structure on Sequential Dynamical Systems,
Simulation and Reduction of Probabilistic Sequential Networks | 14 pages | null | null | null | q-bio.GN math.PR q-bio.MN | null | A probabilistic structure on sequential dynamical systems is introduced here,
the new model will be called Probabilistic Sequential Network, PSN. The
morphisms of Probabilistic Sequential Networks are defined using two algebraic
conditions. It is proved here that two homomorphic Probabilistic Sequential
Networks have the same equilibrium or steady state probabilities if the
morphism is either an epimorphism or a monomorphism. Additionally, the proof of
the set of PSN with its morphisms form the category PSN, having the category of
sequential dynamical systems SDS, as a full subcategory is given. Several
examples of morphisms, subsystems and simulations are given.
| [
{
"version": "v1",
"created": "Fri, 29 Jun 2007 23:34:16 GMT"
},
{
"version": "v2",
"created": "Wed, 30 Apr 2008 13:44:03 GMT"
}
] | 2008-04-30T00:00:00 | [
[
"Avino-Diaz",
"Maria A.",
""
]
] |
0707.0027 | Jared Maruskin | Jared M. Maruskin and Anthony M. Bloch | The Boltzmann-Hamel Equations for Optimal Control | 20 pages, 2 figures | null | null | null | math.OC | null | We extend the Boltzmann-Hamel equations to the optimal control setting,
producing a set of equations for both kinematic and dynamic nonholonomic
optimal control problems. In particular, we will show the dynamic optimal
control problem can be written as a minimal set of 4n-2m first order
differential equations of motion.
| [
{
"version": "v1",
"created": "Fri, 29 Jun 2007 23:44:39 GMT"
}
] | 2007-07-03T00:00:00 | [
[
"Maruskin",
"Jared M.",
""
],
[
"Bloch",
"Anthony M.",
""
]
] |
0707.0028 | Elena Gallo | E. Gallo, S. Migliari, S. Markoff, J. Tomsick, C. Bailyn, S. Berta, R.
Fender, J. Miller-Jones | The spectral energy distribution of quiescent black hole X-ray binaries:
new constraints from Spitzer | accepted by ApJ | Astrophys. J. 670 (2007) 600 | 10.1086/521524 | null | astro-ph | null | (Abridged) Among the various issues that remain open in the field of
accretion onto black hole X-ray binaries (BHBs) is the way the gas accretes at
very low Eddington ratios, in the so-called quiescent regime. While there is
general agreement that the X-rays are produced by a population of high-energy
electrons near to the BH, the controversy comes about in modeling the
contribution from inflowing vs. outflowing particles, and their relative energy
budget. Recent Spitzer observations of three quiescent BHBs have shown evidence
for excess emission with respect to the tail of the companion star between 8-24
micron. We suggest that synchrotron emission from a partially self-absorbed
outflow might be responsible for the observed mid-IR excess, in place of, or in
addition to, thermal emission from circumbinary material. If so, then the jet
synchrotron luminosity exceeds the measured 2-10 keV luminosity by a factor of
a few in these systems. In turn, the mechanical power stored in the jet exceeds
the bolometric X-ray luminosity at least by 4 orders of magnitude. We then
compile the broadband spectral energy distribution (SED) of A0620-00, the
lowest Eddington-ratio stellar mass BH with a known radio counterpart, by means
of simultaneous radio, optical and X-ray observations, and the archival Spitzer
data. We are able to fit the SED of A0620-00 with a `maximally jet-dominated'
model in which the radio through the soft X-rays are dominated by synchrotron
emission, while the hard X-rays are dominated by inverse Compton at the jet
base. The fitted parameters land in a range of values that is reminiscent of
the Galactic Center super-massive BH Sgr A*. Most notably, the inferred ratio
of the jet acceleration rate to local cooling rates is two orders of magnitude
weaker with respect to higher luminosity, hard state sources.
| [
{
"version": "v1",
"created": "Sat, 30 Jun 2007 00:05:16 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Gallo",
"E.",
""
],
[
"Migliari",
"S.",
""
],
[
"Markoff",
"S.",
""
],
[
"Tomsick",
"J.",
""
],
[
"Bailyn",
"C.",
""
],
[
"Berta",
"S.",
""
],
[
"Fender",
"R.",
""
],
[
"Miller-Jones",
"J.",
""
]
] |
0707.0029 | Ruslan Prozorov | Ruslan Prozorov, Matthew D. Vannette, Stephanie A. Law, Sergey L.
Bud'ko, Paul C. Canfield | Zooming into the coexisting regime of ferromagnetism and
superconductivity in ErRh4B4 single crystals | null | Phys. Rev. B. 77 100503(R) (2008) | 10.1103/PhysRevB.77.100503 | null | cond-mat.str-el cond-mat.supr-con | null | High resolution measurements of the dynamic magnetic susceptibility are
reported for ferromagnetic re-entrant superconductor, ErRh$_{4}$B$_{4}$.
Detailed investigation of the coexisting regime reveals unusual
temperature-asymmetric and magnetically anisotropic behavior. The
superconducting phase appears via a series of discontinuous steps upon warming
from the ferromagnetic normal phase, whereas the ferromagnetic phase develops
via a gradual transition. A model based on local field inhomogeneity is
proposed to explain the observations.
| [
{
"version": "v1",
"created": "Sat, 30 Jun 2007 00:12:51 GMT"
}
] | 2009-02-02T00:00:00 | [
[
"Prozorov",
"Ruslan",
""
],
[
"Vannette",
"Matthew D.",
""
],
[
"Law",
"Stephanie A.",
""
],
[
"Bud'ko",
"Sergey L.",
""
],
[
"Canfield",
"Paul C.",
""
]
] |
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