text: 56,58,1308532869837524992,708096751161311232,Priyamvada Natarajan,"For my astro peeps who might have missed my paper on the arXiv today <LINK> Here's the gist of this new channel to make IMBHs *throughout cosmic time* in dense, gas-rich nuclear star clusters (NSCs) via accretion (1/n) <LINK> stellar mass seed BH ~ 5 -10 solar mass forms in the NSC that has ~ 10^4-5 stars. Seed BH behaves like a test particle scatters off stars & gas, inevitably wandering randomly, small excursions from the center, growing very rapidly via wind-fed supra-exponential accretion (2/n) <LINK> In this early growth phase can model motion as a simple harmonic oscillator and compute how much it can grow. As it grows motion gets damped due to drag from gas and dynamical friction, motion transits to that of a damped harmonic oscillator, continues growing but...(3/n) Growth could get disrupted..can estimate final BH mass if prematurely terminated (25 - 100 solar masses). If it continues then it reaches the center, settles down to being a stationary BH at this point it would be between 100 - 1000 solar masses (4/n) Of course, depending on the availability of gas could keep growing till gas supply is exhausted which in typical NSCs can easily bring it 10^4-5 solar masses. So here is a schematic of the possible outcomes -- (5/n) <LINK> What the model offers is a continual formation mechanism for IMBHs as NSCs seen in a large fraction of galaxies, they are huddled in the center of galaxies but some are off-center too. Therefore, NSCs can act as incubators for the formation of IMBHs - channel can explain....(6/n) (i) central & off-center IMBHs are now detected in low-mass dwarf galaxies (ii) premature termination can account for formation of BHs in the mass gap 50 - 150 solar masses, sources like GW190521. In this model IMBHs grow by accretion not mergers (previous work) in NSCs. (7/n) @harshalhb_india model not yet set up to do demographic predictions like the merger scenarios..just worked out the physics at the moment - but yes plan is to look at all observables...",https://arxiv.org/abs/2009.09156,"While the formation of the first black holes at high redshift is reasonably well understood though debated, massive black hole formation at later cosmic epochs has not been adequately explored. We present a gas accretion driven mechanism that can build up black hole masses rapidly in dense, gas-rich nuclear star clusters (NSCs). Wind-fed supra-exponential accretion of an initially wandering black hole in NSCs can lead to extremely fast growth, scaling stellar mass remnant seed black holes up to intermediate mass black holes (IMBHs). Operating throughout cosmic time, growth via this new channel is modulated by the gas supply, and premature termination results in the formation of lower mass black holes with masses in the range of 50 - few 100 solar masses, filling in the so-called mass gap. However, in most gas-rich NSCs, growth is unimpeded, inevitably leading to the formation of IMBHs with masses ranging from 100 - 100,000 solar masses. A spate of new detection spanning the full range of the IMBH mass function - from the LIGO-VIRGO source GW190521 to the emerging population of 10^5 solar mass black holes harbored in low-mass dwarf galaxies - are revealing this elusive population. Naturally accounting for the detected presence of off-center IMBHs in low-mass dwarfs, this new pathway also predicts the existence of an extensive population of wandering non-central black holes in more massive galaxies would be detectable via tidal disruption events and as GW sources. Gas-rich NSCs serve as incubators for the continual formation of black holes over a wide range in mass throughout cosmic time. ",A new channel to form IMBHs throughout cosmic time,8,"[""For my astro peeps who might have missed my paper on the arXiv today <LINK>\nHere's the gist of this new channel to make IMBHs *throughout cosmic time* in dense, gas-rich nuclear star clusters (NSCs) via accretion (1/n) <LINK>"", 'stellar mass seed BH ~ 5 -10 solar mass forms in the NSC that has ~ 10^4-5 stars. Seed BH behaves like a test particle scatters off stars &amp; gas, inevitably wandering randomly, small excursions from the center, growing very rapidly via wind-fed supra-exponential accretion (2/n) https://t.co/9xYc53lpIb', 'In this early growth phase can model motion as a simple harmonic oscillator and compute how much it can grow. As it grows motion gets damped due to drag from gas and dynamical friction, motion transits to that of a damped harmonic oscillator, continues growing but...(3/n)', 'Growth could get disrupted..can estimate final BH mass if prematurely terminated (25 - 100 solar masses). If it continues then it reaches the center, settles down to being a stationary BH at this point it would be between 100 - 1000 solar masses (4/n)', 'Of course, depending on the availability of gas could keep growing till gas supply is exhausted which in typical NSCs can easily bring it 10^4-5 solar masses. So here is a schematic of the possible outcomes -- (5/n) https://t.co/i9QNCMhWvi', 'What the model offers is a continual formation mechanism for IMBHs as NSCs seen in a large fraction of galaxies, they are huddled in the center of galaxies but some are off-center too. Therefore, NSCs can act as incubators for the formation of IMBHs - channel can explain....(6/n)', '(i) central &amp; off-center IMBHs are now detected in low-mass dwarf galaxies (ii) premature termination can account for formation of BHs in the mass gap 50 - 150 solar masses, sources like GW190521. In this model IMBHs grow by accretion not mergers (previous work) in NSCs. (7/n)', '@harshalhb_india model not yet set up to do demographic predictions like the merger scenarios..just worked out the physics at the moment - but yes plan is to look at all observables...']",20,09,2002