scholarly journals Multiplicity functions of quasars: predictions from the MassiveBlackII simulation

2020 ◽  
Vol 492 (4) ◽  
pp. 5620-5633
Author(s):  
Aklant K Bhowmick ◽  
Tiziana Di Matteo ◽  
Adam D Myers

ABSTRACT We examine multiple active galactic nucleus (AGN) systems (triples and quadruples, in particular) in the MassiveBlackII simulation over a redshift range of 0.06 ≲ z ≲ 4. We identify AGN systems (with bolometric luminosity $L_{\mathrm{bol}}\gt 10^{42}~\mathrm{erg\, s}^{-1}$) at different scales (defined by the maximum distance between member AGNs) to determine the AGN multiplicity functions. This is defined as the volume/surface density of AGN systems per unit richness R, the number of AGNs in a system. We find that gravitationally bound multiple AGN systems tend to populate scales of ${\lesssim}0.7~\mathrm{cMpc}\, h^{-1}$; this corresponds to angular separations of ≲100 arcsec and a line-of-sight velocity difference ${\lesssim}200~\mathrm{km\, s}^{-1}$. The simulation contains ∼10 and ∼100 triples/quadruples per deg2 up to depths of DESI (g ≲ 24) and LSST (g ≲ 26) imaging, respectively; at least $20{{\ \rm per\ cent}}$ of these should be detectable in spectroscopic surveys. The simulated quasar ($L_{\mathrm{bol}}\gt 10^{44}~\mathrm{erg\, s}^{-1}$) triples and quadruples predominantly exist at 1.5 ≲ z ≲ 3. Their members have black hole masses $10^{6.5}\lesssim M_{\mathrm{ bh}}\lesssim 10^{9}~\mathrm{M}_{\odot }\, h^{-1}$ and live in separate (one central and multiple satellite) galaxies with stellar masses $10^{10}\lesssim M_{*}\lesssim 10^{12}~\mathrm{M}_{\odot }\, h^{-1}$. They live in the most massive haloes (e.g. ${\sim}10^{13}~\mathrm{M}_{\odot }\, h^{-1}$ at z = 2.5; ${\sim}10^{14}~\mathrm{M}_{\odot }\, h^{-1}$ at z = 1) in the simulation. Their detections provide an exciting prospect for understanding massive black hole growth and their merger rates in galaxies in the era of multimessenger astronomy.

2009 ◽  
Vol 5 (S267) ◽  
pp. 266-266
Author(s):  
Andreas Schulze ◽  
Lutz Wisotzki

The observed relations between the black hole mass and the properties of the spheroidal galaxy component imply a close connection between the growth of supermassive black holes and the evolution of their host galaxies. An effective approach to study black hole growth is to measure black hole masses and Eddington ratios of well-defined type 1 AGN samples and determine the underlying distribution functions.


2019 ◽  
Vol 492 (2) ◽  
pp. 1991-2016 ◽  
Author(s):  
M Marinello ◽  
R A Overzier ◽  
H J A Röttgering ◽  
J D Kurk ◽  
C De Breuck ◽  
...  

ABSTRACT We present Very Large Telescope/Spectrograph for INtegral Field Observations in the Near Infrared (VLT/SINFONI) observations of 35 quasars at 2.1 < z < 3.2, the majority of which were selected from the Clusters Around Radio-Loud AGN (CARLA) survey. CARLA quasars have large C iv-based black hole masses (MBH > 109 M⊙) and powerful radio emission ($P_{500\, \rm MHz}$ > 27.5 W Hz−1). We estimate H α-based MBH, finding a scatter of 0.35 dex compared to C iv. We evaluate several recipes for correcting C iv-based masses, which reduce the scatter to 0.24 dex. The radio power of the radio-loud quasars is at most weakly correlated with the interconnected quantities H αwidth, L5100, and MBH, suggesting that it is governed by different physical processes. However, we do find a strong inverse correlation between C iv blueshift and radio power linked to higher Eddington ratios and L5100. Under standard assumptions, the black hole (BH) growth time is longer than the cosmic age for many CARLA quasars, suggesting that they must have experienced more efficient growth in the past. If these BHs were growing from seeds since the epoch of reionization, it is possible that they grew at the Eddington limit like the quasars at z ∼ 6–7, and then continued to grow at the reduced rates observed until z ∼ 2–3. Finally, we study the relation between MBH and environment, finding a weak positive correlation between MBH and galaxydensity measured by CARLA.


2007 ◽  
Vol 3 (S245) ◽  
pp. 63-66 ◽  
Author(s):  
T. J. Cox ◽  
J. Younger ◽  
L. Hernquist ◽  
P. F. Hopkins

AbstractThe hierarchical formation of structure suggests that dark halos, and the galaxies they host, are shaped by their merging history. While the idea that mergers between galaxies of equal mass, i.e., major merger, produce elliptical galaxies has received considerable attention, he galaxies that result from minor merger, i.e., mergers between galaxies with a large mass ratio, is much less understood. We have performed a large number of numerical simulations of minor mergers, including cooling, star formation, and black hole growth in order to study this process in more detail. This talk will present some preliminary results of this study, and in particular, the morphology and kinematics of minor merger remnants.


2016 ◽  
Vol 458 (2) ◽  
pp. 1402-1416 ◽  
Author(s):  
MaoSheng Liu ◽  
Tiziana Di Matteo ◽  
Yu Feng

2009 ◽  
Vol 5 (S267) ◽  
pp. 273-282
Author(s):  
Andrew King

AbstractI review accretion and outflow in active galactic nuclei. Accreti4on appears to occur in a series of very small-scale, chaotic events, whose gas flows have no correlation with the large-scale structure of the galaxy or with each other. The accreting gas has extremely low specific angular momentum and probably represents only a small fraction of the gas involved in a galaxy merger, which may be the underlying driver.Eddington accretion episodes in AGN must be common in order for the supermassive black holes to grow. I show that they produce winds with velocities v ~ 0.1c and ionization parameters implying the presence of resonance lines of helium-like and hydrogen-like iron. The wind creates a strong cooling shock as it interacts with the interstellar medium of the host galaxy, and this cooling region may be observable in an inverse Compton continuum and lower-excitation emission lines associated with lower velocities. The shell of matter swept up by the shocked wind stalls unless the black hole mass has reached the value Mσ implied by the M–σ relation. Once this mass is reached, further black hole growth is prevented. If the shocked gas did not cool as asserted above, the resulting (“energy-driven”) outflow would imply a far smaller SMBH mass than actually observed. Minor accretion events with small gas fractions can produce galaxy-wide outflows, including fossil outflows in galaxies where there is little current AGN activity.


Sign in / Sign up

Export Citation Format

Share Document