Observations of quasars at $z> 6$ suggest the presence of black holes with a
few times $10^9 ~M_ødot$. Numerous models have been proposed to explain
their existence including the direct collapse which provides massive seeds of
$10^5~M_ødot$. The isothermal direct collapse requires a strong
Lyman-Werner flux to quench $H_2$ formation in massive primordial halos. In
this study, we explore the impact of trace amounts of metals and dust
enrichment. We perform three dimensional cosmological simulations for two halos
of $> 10^7~M_ødot$ with $Z/Z_ødot= 10^-4-10^-6$ illuminated
by an intense Lyman Werner flux of $J_21=10^5$. Our results show that
initially the collapse proceeds isothermally with $T 8000$ K but dust
cooling becomes effective at densities of $10^8-10^12 ~cm^-3$ and
brings the gas temperature down to a few 100-1000 K for $Z/Z_ødot \geq
10^-6$. No gravitationally bound clumps are found in $Z/Z_ødot łeq
10^-5$ cases by the end of our simulations in contrast to the case with $\rm
Z/Z_ødot = 10^-4$. Large inflow rates of $0.1~M_ødot/yr$ are
observed for $Z/Z_ødot 10^-5$ similar to a zero-metallicity case
while for $Z/Z_ødot = 10^-4$ the inflow rate starts to decline
earlier. For given large inflow rates a central star of $\sim
10^4~M_ødot$ may form for $Z/Z_ødot 10^-5$. Even in the case
of strong fragmentation, a dense stellar cluster is expected to form which may
later collapse into a black hole seed of up to $1000~M_ødot$.
Description
[1509.07034] Impact of dust cooling on direct collapse black hole formation
%0 Generic
%1 latif2015impact
%A Latif, M. A.
%A Omukai, K.
%A Habouzit, M.
%A Schleicher, D. R. G.
%A Volonteri, M.
%D 2015
%K blackhole collapse cooling direct dust formation
%T Impact of dust cooling on direct collapse black hole formation
%U http://arxiv.org/abs/1509.07034
%X Observations of quasars at $z> 6$ suggest the presence of black holes with a
few times $10^9 ~M_ødot$. Numerous models have been proposed to explain
their existence including the direct collapse which provides massive seeds of
$10^5~M_ødot$. The isothermal direct collapse requires a strong
Lyman-Werner flux to quench $H_2$ formation in massive primordial halos. In
this study, we explore the impact of trace amounts of metals and dust
enrichment. We perform three dimensional cosmological simulations for two halos
of $> 10^7~M_ødot$ with $Z/Z_ødot= 10^-4-10^-6$ illuminated
by an intense Lyman Werner flux of $J_21=10^5$. Our results show that
initially the collapse proceeds isothermally with $T 8000$ K but dust
cooling becomes effective at densities of $10^8-10^12 ~cm^-3$ and
brings the gas temperature down to a few 100-1000 K for $Z/Z_ødot \geq
10^-6$. No gravitationally bound clumps are found in $Z/Z_ødot łeq
10^-5$ cases by the end of our simulations in contrast to the case with $\rm
Z/Z_ødot = 10^-4$. Large inflow rates of $0.1~M_ødot/yr$ are
observed for $Z/Z_ødot 10^-5$ similar to a zero-metallicity case
while for $Z/Z_ødot = 10^-4$ the inflow rate starts to decline
earlier. For given large inflow rates a central star of $\sim
10^4~M_ødot$ may form for $Z/Z_ødot 10^-5$. Even in the case
of strong fragmentation, a dense stellar cluster is expected to form which may
later collapse into a black hole seed of up to $1000~M_ødot$.
@misc{latif2015impact,
abstract = {Observations of quasars at $z> 6$ suggest the presence of black holes with a
few times $\rm 10^9 ~M_{\odot}$. Numerous models have been proposed to explain
their existence including the direct collapse which provides massive seeds of
$\rm 10^5~M_{\odot}$. The isothermal direct collapse requires a strong
Lyman-Werner flux to quench $\rm H_2$ formation in massive primordial halos. In
this study, we explore the impact of trace amounts of metals and dust
enrichment. We perform three dimensional cosmological simulations for two halos
of $\rm > 10^7~M_{\odot}$ with $\rm Z/Z_{\odot}= 10^{-4}-10^{-6}$ illuminated
by an intense Lyman Werner flux of $\rm J_{21}=10^5$. Our results show that
initially the collapse proceeds isothermally with $\rm T \sim 8000$ K but dust
cooling becomes effective at densities of $\rm 10^{8}-10^{12} ~cm^{-3}$ and
brings the gas temperature down to a few 100-1000 K for $\rm Z/Z_{\odot} \geq
10^{-6}$. No gravitationally bound clumps are found in $\rm Z/Z_{\odot} \leq
10^{-5}$ cases by the end of our simulations in contrast to the case with $\rm
Z/Z_{\odot} = 10^{-4}$. Large inflow rates of $\rm \geq 0.1~M_{\odot}/yr$ are
observed for $\rm Z/Z_{\odot} \leq 10^{-5}$ similar to a zero-metallicity case
while for $\rm Z/Z_{\odot} = 10^{-4}$ the inflow rate starts to decline
earlier. For given large inflow rates a central star of $\rm \sim
10^4~M_{\odot}$ may form for $\rm Z/Z_{\odot} \leq 10^{-5}$. Even in the case
of strong fragmentation, a dense stellar cluster is expected to form which may
later collapse into a black hole seed of up to $\rm 1000~M_{\odot}$.},
added-at = {2015-09-24T10:28:33.000+0200},
author = {Latif, M. A. and Omukai, K. and Habouzit, M. and Schleicher, D. R. G. and Volonteri, M.},
biburl = {https://www.bibsonomy.org/bibtex/263a44a43eb918a4420c654f4dbba7e12/miki},
description = {[1509.07034] Impact of dust cooling on direct collapse black hole formation},
interhash = {2b3e35c7980f69f1bfdf90ae31841f8a},
intrahash = {63a44a43eb918a4420c654f4dbba7e12},
keywords = {blackhole collapse cooling direct dust formation},
note = {cite arxiv:1509.07034Comment: Submitted for publication in MNRAS, comments are welcome},
timestamp = {2015-09-24T10:28:33.000+0200},
title = {Impact of dust cooling on direct collapse black hole formation},
url = {http://arxiv.org/abs/1509.07034},
year = 2015
}