FORMATION OF THE FIRST NUCLEAR CLUSTERS AND MASSIVE BLACK HOLES AT HIGH REDSHIFT

By B. Devecchi, M. Volonteri. 2008

195 citations recorded by the source corpus.

We present a model for the formation of massive black holes (∼1000 M☉) due to stellar-dynamical processes in the first stellar clusters formed at early cosmic times (z ∼ 10–20). These black holes are likely candidates as seeds for the supermassive black holes detected in quasars and nearby quiescent galaxies. The high redshift black hole seeds form as a result of multiple successive instabilities that occur in low metallicity (Z ∼ 10−5 Z☉) protogalaxies. We focus on relatively massive halos at high redshift (Tvir > 104 K, z ≳ 10) after the very first stars in the universe have completed their evolution. This set of assumptions ensures that (1) atomic hydrogen cooling can contribute to the gas cooling process, (2) a UV field has been created by the first stars, and (3) the gas inside the halo has been mildly polluted by the first metals. The second condition implies that at low density H2 is dissociated and does not contribute to cooling. The third condition sets a minimum threshold density for fragmentation, so that stars form efficiently only in the very inner core of the protogalaxy. Within this core, very compact stellar clusters form. The typical star cluster masses are of order 105 M☉ and the typical half mass radii ∼1 pc. A large fraction of these very dense clusters undergoes core collapse before stars are able to complete stellar evolution. Runaway star–star collisions eventually lead to the formation of a very massive star, leaving behind a massive black hole remnant. Clusters unstable to runaway collisions are always the first, less massive ones that form. As the metallicity of the universe increases, the critical density for fragmentation decreases and stars start to form in the entire protogalactic disk so that (1) accretion of gas in the center is no longer efficient and (2) the core collapse timescale increases. Typically, a fraction ∼0.05 of protogalaxies at z ∼ 10–20 form black hole seeds, with masses ∼1000–2000 M☉, leading to a mass density in seeds of a few ≃102 M☉/Mpc−3. This density allows enough room for black hole growth by accretion during the quasar epoch.

Subfields: Astronomy and Astrophysics

View Paper: https://www.semanticscholar.org/paper/c0d43e93a3b7b1150abafd8dd52de8630df49c29

How researchers see this paper

The researchers whose trusted networks rank it highest, strongest advocate first. Every researcher gets a different order.

In Astronomy and Astrophysics

Citations in the corpus

Formation of Supermassive Black Hole Seeds (2016, background): “On the other hand for higher metallicities fragmentation already occurs at densities < 103 cm−3 and results in the core collapse time longer than 3 Myrs (Omukai et al. 2008; Devecchi & Volonteri 2009; Devecchi et al. 2012).”
Tracing the cosmic growth of supermassive black holes to z ∼ 3 with Herschel (2014, background): “Though the detailed mechanisms that are the source of the powerful nuclear activity are still debated (Rees 1978; Lodato & Natarajan 2007; Devecchi & Volonteri 2009; Volonteri & Begelman 2010; Ball et al. 2011; Natarajan 2011), it is believed that it is mainly due to mass accretion onto a super…”
Observational evidence for intermediate-mass black holes (2017, background): “Frequent stellar mergers within the cluster can lead to the formation of a supermassive star that will collapse into a BH of ∼ 102−104 M (Devecchi & Volonteri 2009).”
Titans of the early Universe: The Prato statement on the origin of the first supermassive black holes (2018, background): “…of a primordial atomiccooling halo into a DCBH (Bromm & Loeb 2003; Shang et al. 2010; Johnson et al. 2012), or (iii) the formation of a very massive star from runaway stellar mergers in a dense cluster (Omukai, Schneider, & Haiman 2008; Devecchi & Volonteri 2009; Davies, Miller, & Bellovary 2011).”
Evidence for heavy-seed origin of early supermassive black holes from a z ≈ 10 X-ray quasar (2023, background): “These environments could, in turn, serve as further new incubators for the formation of intermediate-mass BHs facilitated by stellar and gas dynamical processes that occur in them; from a range of stellar dynamical interactions that can occur in these dense environments[30] as well as extremely rapi”
What drives the growth of black holes (2011, background): “…candidate mechanism proposes that the seed BH formation is preceded by the formation of dense stellar clusters, the centers of which then undergo runaway merging due to stellar-dynamical processes that produces a BH (e.g., Devecchi & Volonteri, 2009; Devecchi et al., 2010; Davies et al., 2011).”
Hyper-Eddington accretion flows on to massive black holes (2015, background): “…a massive BH could form via runaway stellar collisions in a globular cluster (Sanders 1970; Portegies Zwart et al. 2004; Freitag, Gürkan & Rasio 2006) and in protogalaxies (Omukai, Schneider & Haiman 2008; Devecchi & Volonteri 2009; Katz, Sijacki & Haehnelt 2015; Yajima & Khochfar 2016).”
Blossoms from black hole seeds: properties and early growth regulated by supernova feedback (2016, background): “For the nuclear cluster scenario the metallicity range is the key parameter allowing for formation of a BH with mass ∼ 103 M (see Devecchi & Volonteri 2009), once a dense cluster of stars forms in the clump.”
Doing Science with eLISA: Astrophysics and Cosmology in the Millihertz Regime (2012, background): “as the origin of black holes (Mayer et al., 2010). The subsequent step is to follow the evolution of the black hole seeds according to the growth of the halos they inhabit, and the mode of accretion (Devecchi and Volonteri, 2009, Volonteri and Begelman, 2010, Volonteri et al., 2008). This is an inhe”
Physical Properties of 15 Quasars at z ≳ 6.5 (2017, background): “…(e.g., Bond et al. 1984, Alvarez et al. 2009, Valiante et al. 2016), the co-action of dynamical processes, gas collapse and star formation (e.g., Devecchi & Volonteri 2009), or the rapid growth of stellar-mass seeds via episodes of super-Eddington, radiatively inefficient accretion (e.g., Madau…”
Stellar Dynamics and Stellar Phenomena Near a Massive Black Hole (2017, background): “…a very massive star by mergers, which will retain most of its mass as it collapses directly into a black hole (BH) (Omukai, Schneider & Haiman 2008; Devecchi & Volonteri 2009; Davies, Miller & Bellovary 2011), or a stellar BH that is launched into a phase of supra-exponential accretion from the…”
Formation of supermassive black holes (2010, background): “Devecchi and Volonteri (2009) find that typically a fraction ∼ 0.05 of protogalaxies at z ∼ 10− 20 form black hole seeds, with masses ∼ 1000 − 2000 M , leading to a mass density in seeds of a few ' 10(2) M /Mpc−3. Most of the assumptions in Devecchi and Volonteri (2009) have been conservative, but s”
Black hole formation in the early Universe (2013, background): “…of young dense stellar clusters due to relativistic instability (Portegies Zwart et al. 2004; Omukai, Schneider & Haiman 2008; Devecchi & Volonteri 2009) but this can happen only if the Universe is enriched with trace amounts of metals after the formation of the first stars…”