scholarly journals The Assembly of the First Massive Black Holes

2020 ◽  
Vol 58 (1) ◽  
pp. 27-97 ◽  
Author(s):  
Kohei Inayoshi ◽  
Eli Visbal ◽  
Zoltán Haiman

The existence of ∼109M⊙ supermassive black holes (SMBHs) within the first billion years of the Universe has stimulated numerous ideas for the prompt formation and rapid growth of black holes (BHs) in the early Universe. Here, we review ways in which the seeds of massive BHs may have first assembled, how they may have subsequently grown as massive as ∼109M⊙, and how multimessenger observations could distinguish between different SMBH assembly scenarios. We conclude the following: ▪  The ultrarare ∼109 M⊙ SMBHs represent only the tip of the iceberg. Early BHs likely fill a continuum from the stellar-mass (∼10M⊙) to the supermassive (∼109) regimes, reflecting a range of initial masses and growth histories. ▪  Stellar-mass BHs were likely left behind by the first generation of stars at redshifts as high as ∼30, but their initial growth typically was stunted due to the shallow potential wells of their host galaxies. ▪  Conditions in some larger, metal-poor galaxies soon became conducive to the rapid formation and growth of massive seed holes, via gas accretion and by mergers in dense stellar clusters. ▪  BH masses depend on the environment (such as the number and properties of nearby radiation sources and the local baryonic streaming velocity) and on the metal enrichment and assembly history of the host galaxy. ▪  Distinguishing between assembly mechanisms will be difficult, but a combination of observations by the Laser Interferometer Space Antenna (probing massive BH growth via mergers) and by deep multiwavelength electromagnetic observations (probing growth via gas accretion) is particularly promising.

2012 ◽  
Vol 2012 ◽  
pp. 1-11 ◽  
Author(s):  
Peter Erwin ◽  
Dimitri Alexei Gadotti

Studies have suggested that there is a strong correlation between the masses of nuclear star clusters (NSCs) and their host galaxies, a correlation which is said to be an extension of the well-known correlations between supermassive black holes (SMBHs) and their host galaxies. But careful analysis of disk galaxies—including 2D bulge/disk/bar decompositions—shows that while SMBHs correlate with the stellar mass of thebulgecomponent of galaxies, the masses of NSCs correlate much better with thetotalgalaxy stellar mass. In addition, the mass ratioMNSC/M⋆, totfor NSCs in spirals (at least those with Hubble types Sc and later) is typically an order of magnitude smaller than the mass ratioMBH/M⋆, bulof SMBHs. The absence of a universal “central massive object” correlation argues against common formation and growth mechanisms for both SMBHs and NSCs. We also discuss evidence for a break in the NSC-host galaxy correlation, galaxies with Hubble types earlier than Sbc appear to host systematically more massive NSCs than do types Sc and later.


2019 ◽  
Vol 15 (S359) ◽  
pp. 35-36
Author(s):  
Paramita Barai

AbstractGas accretion onto central supermassive black holes of active galaxies and resulting energy feedback, is an important component of galaxy evolution, whose details are still unknown especially at early cosmic epochs. We investigate BH growth and feedback in quasar-host galaxies at z ⩾ 6 by performing cosmological hydrodynamical simulations. We simulate the 2R200 region around a 2 × 1012Mʘ halo at z = 6, inside a (500 Mpc)3 comoving volume, using the zoom-in technique. We find that BHs accrete gas at the Eddington rate over z = 9–6. At z = 6, our most-massive BH has grown to MBH = 4 × 109 Mʘ. Star-formation is quenched over z = 8–6.


2009 ◽  
Vol 5 (S267) ◽  
pp. 26-33 ◽  
Author(s):  
Marta Volonteri

AbstractMassive black holes (MBHs) are nowadays believed to reside in most local galaxies. Studies have also established a number of relations between the MBH mass and properties of the host galaxy such as bulge mass and velocity dispersion. These results suggest that central MBHs, while much less massive than their hosts (~ 0.1%), are linked to the evolution of galactic structure. When did it all start? In hierarchical cosmologies, a single big galaxy today can be traced back to the stage when it was split up in hundreds of smaller components. Did MBH seeds form with the same efficiency in small proto-galaxies, or did their formation have to await the buildup of substantial galaxies with deeper potential wells? I briefly review here some of the physical processes that are conducive to the evolution of the massive black hole population. I will discuss black hole formation processes for “seed” black holes that are likely to take place at early cosmic epochs, and possible observational tests of these scenarios.


2012 ◽  
Vol 2012 ◽  
pp. 1-11 ◽  
Author(s):  
Roberto Decarli ◽  
Renato Falomo ◽  
Jari K. Kotilainen ◽  
Tomi Hyvönen ◽  
Michela Uslenghi ◽  
...  

TheMBH-Mhostrelation in quasars has been probed only in a limited parameter space, namely, atMBH∼109 M⊙andMhost∼1012 M⊙. Here we present a study of 26 quasars laying in the low-mass end of the relation, down toMBH∼107 M⊙. We selected quasars from the SDSS and HST-FOS archives, requiring modestMBH(as derived through the virial paradigm). We imaged our sources inHband from the Nordic Optical Telescope. The quasar host galaxies have been resolved in 25 out of 26 observed targets. Host galaxy luminosities and stellar masses are computed, under reasonable assumptions on their star formation histories. Combining these results with those from our previous studies, we manage to extend the sampled parameter space of theMBH-Mhostrelation in quasars. The relation holds over 2 dex in both the parameters. For the first time, we are able to measure the slope of theMBH-Mhostrelation in quasars. We find that it is consistent with the linear case (similarly to what observed in quiescent galaxies). We do not find any evidence of a population of massive black holes lying below the relation.


2009 ◽  
Vol 5 (S267) ◽  
pp. 34-39
Author(s):  
J. K. Kotilainen ◽  
R. Decarli ◽  
R. Falomo ◽  
A. Treves ◽  
M. Labita ◽  
...  

AbstractWe study the evolution of the MBH/Mhost relation up to z = 3 for a sample of 96 quasars with known host galaxy luminosities. Black hole masses are estimated assuming virial equilibrium in the broad-line regions, while the host galaxy masses are inferred from their luminosities. With this data, we are able to pin down the evolution of the MBH/Mhost relation over 85% of the age of the universe. While the MBH/Lhost relation remains nearly unchanged, taking into account the aging of the stellar population, we find that the MBH/Mhost ratio (Γ) increases by a factor ~ 7 from z = 0 to z = 3. We show that the evolution of Γ is independent of radio loudness and quasar luminosity. We propose that the most massive black holes, in their quasar phase at high-redshift, become extremely rare objects in host galaxies of similar mass in the local universe.


2020 ◽  
Vol 501 (1) ◽  
pp. 269-280
Author(s):  
Xuheng Ding ◽  
Tommaso Treu ◽  
Simon Birrer ◽  
Adriano Agnello ◽  
Dominique Sluse ◽  
...  

ABSTRACT One of the main challenges in using high-redshift active galactic nuclei (AGNs) to study the correlations between the mass of a supermassive black hole ($\mathcal {M}_{\rm BH}$) and the properties of its active host galaxy is instrumental resolution. Strong lensing magnification effectively increases instrumental resolution and thus helps to address this challenge. In this work, we study eight strongly lensed AGNs with deep Hubble Space Telescope imaging, using the lens modelling code lenstronomy to reconstruct the image of the source. Using the reconstructed brightness of the host galaxy, we infer the host galaxy stellar mass based on stellar population models. $\mathcal {M}_{\rm BH}$ are estimated from broad emission lines using standard methods. Our results are in good agreement with recent work based on non-lensed AGNs, demonstrating the potential of using strongly lensed AGNs to extend the study of the correlations to higher redshifts. At the moment, the sample size of lensed AGNs is small and thus they provide mostly a consistency check on systematic errors related to resolution for non-lensed AGNs. However, the number of known lensed AGNs is expected to increase dramatically in the next few years, through dedicated searches in ground- and space-based wide-field surveys, and they may become a key diagnostic of black holes and galaxy co-evolution.


2019 ◽  
Vol 15 (S356) ◽  
pp. 143-143
Author(s):  
Jaya Maithil ◽  
Michael S. Brotherton ◽  
Bin Luo ◽  
Ohad Shemmer ◽  
Sarah C. Gallagher ◽  
...  

AbstractActive Galactic Nuclei (AGN) exhibit multi-wavelength properties that are representative of the underlying physical processes taking place in the vicinity of the accreting supermassive black hole. The black hole mass and the accretion rate are fundamental for understanding the growth of black holes, their evolution, and the impact on the host galaxies. Recent results on reverberation-mapped AGNs show that the highest accretion rate objects have systematic shorter time-lags. These super-Eddington accreting massive black holes (SEAMBHs) show BLR size 3-8 times smaller than predicted by the Radius-Luminosity (R-L) relationship. Hence, the single-epoch virial black hole mass estimates of highly accreting AGNs have an overestimation of a factor of 3-8 times. SEAMBHs likely have a slim accretion disk rather than a thin disk that is diagnostic in X-ray. I will present the extreme X-ray properties of a sample of dozen of SEAMBHs. They indeed have a steep hard X-ray photon index, Γ, and demonstrate a steeper power-law slope, ασx.


2019 ◽  
Vol 15 (S356) ◽  
pp. 376-376
Author(s):  
Ingyin Zaw

AbstractNuclear black holes in dwarf galaxies are important for understanding the low end of the supermassive black hole mass distribution and the black hole-host galaxy scaling relations. IC 750 is a rare system which hosts an AGN, found in ˜0.5% of dwarf galaxies, with circumnuclear 22 GHz water maser emission, found in ˜3–5% of Type 2 AGNs. Water masers, the only known tracer of warm, dense gas in the center parsec of AGNs resolvable in position and velocity, provide the most precise and accurate mass measurements of SMBHs outside the local group. We have mapped the maser emission in IC 750 and find that it traces a nearly edge-on warped disk, 0.2 pc in diameter. The central black hole has an upper limit mass of ˜1 × 105 M⊙ and a best fit mass of ˜8 × 104 M⊙, one to two orders of magnitude below what is expected from black hole-galaxy scaling relations. This has implications for models of black hole seed formation in the early universe, the growth of black holes, and their co-evolution with their host galaxies.


2014 ◽  
Vol 784 (2) ◽  
pp. L38 ◽  
Author(s):  
Piero Madau ◽  
Francesco Haardt ◽  
Massimo Dotti

Sign in / Sign up

Export Citation Format

Share Document