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121. BeppoSAX HELLAS survey. V.
ID:
ivo://CDS.VizieR/J/ApJ/570/100
Title:
BeppoSAX HELLAS survey. V.
Short Name:
J/ApJ/570/100
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present optical spectroscopic identifications of hard X-ray (5-10keV) selected sources belonging to the High-Energy Large-Area Survey sample obtained with BeppoSAX down to a 5-10keV flux limit of F(5-10kev)~3x10^-14^erg/cm^2^/s. The sample consists of 118 sources. There are 25 sources that have been identified through correlations with catalogs of known sources. A spectroscopic identification for 49 more has been searched for with the telescope. The results of 13 fields were empty down to R=21. There were 37 sources identified as type 1 active galactic nuclei (AGNs) and nine as type 2 AGNs. The remaining sources are five narrow emission-line galaxies, six clusters, two BL Lac objects, one radio galaxy, and one star.
122. BH masses and Eddington ratios of Type 2 QSOs
ID:
ivo://CDS.VizieR/J/ApJ/859/116
Title:
BH masses and Eddington ratios of Type 2 QSOs
Short Name:
J/ApJ/859/116
Date:
21 Oct 2021
Publisher:
CDS
Description:
Type 2 quasars are an important constituent of active galaxies, possibly representing the evolutionary precursors of traditionally studied type 1 quasars. We characterize the black hole (BH) mass (MBH) and Eddington ratio (Lbol/LEdd) for 669 type 2 quasars selected from the Sloan Digital Sky Survey, using BH masses estimated from the MBH-{sigma}* relation and bolometric corrections scaled from the extinction-corrected [OIII]{lambda}5007 luminosity. When stellar velocity dispersions cannot be measured directly from the spectra, we estimate them from the core velocity dispersions of the narrow emission lines [OII]{lambda}{lambda}3726,3729, [SII]{lambda}{lambda}6716,6731, and [OIII]{lambda}5007, which are shown to trace the gravitational potential of the stars. Energy input from the active nucleus still imparts significant perturbations to the gas kinematics, especially to high-velocity, blueshifted wings. Nonvirial motions in the gas become most noticeable in systems with high Eddington ratios. The BH masses of our sample of type 2 quasars range from MBH~10^6.5^ to 10^10.4^M_{sun}_ (median 10^8.2^M_{sun}_). Type 2 quasars have characteristically large Eddington ratios (Lbol/LEdd~10^-2.9^-10^1.8^; median 10^-0.7^), slightly higher than in type 1 quasars of similar redshift; the luminosities of ~20% of the sample formally exceed the Eddington limit. The high Eddington ratios may be consistent with the notion that obscured quasars evolve into unobscured quasars.
123. BH masses & host galaxy dispersion vel.
ID:
ivo://CDS.VizieR/J/ApJ/831/134
Title:
BH masses & host galaxy dispersion vel.
Short Name:
J/ApJ/831/134
Date:
21 Oct 2021
Publisher:
CDS
Description:
According to the virial theorem, all gravitational systems in equilibrium sit on a plane in the three-dimensional parameter space defined by their mass, size, and second moment of the velocity tensor. While these quantities cannot be directly observed, there are suitable proxies: the luminosity L_k_, half-light radius R_e_, and dispersion {sigma}_e_. These proxies indeed lie on a very tight fundamental plane (FP). How do the black holes (BHs) in the centers of galaxies relate to the FP? Their masses are known to exhibit no strong correlation with total galaxy mass, but they do correlate weakly with bulge mass (when present), and extremely well with the velocity dispersion through the M_{bullet}_{propto}{sigma}_e_^5.4^ relation. These facts together imply that a tight plane must also exist defined by BH mass, total galaxy mass, and size. Here, I show that this is indeed the case using a heterogeneous set of 230 BHs. The sample includes BHs from zero to 10 billion solar masses and host galaxies ranging from low surface brightness dwarfs, through bulgeless disks, to brightest cluster galaxies. The resulting BH-size-luminosity relation M_{bullet}_{propto}(L_k_/R_e_)^3.8^ has the same amount of scatter as the M_*_-{sigma} relation and is aligned with the galaxy FP, such that it is just a reprojection of {sigma}_e_. The inferred BH-size-mass relation is M_{bullet}_{propto}(M_*_/R_e_)^2.9^. These relationships are universal and extend to galaxies without bulges. This implies that the BH is primarily correlated with its global velocity dispersion and not with the properties of the bulge. I show that the classical bulge-mass relation is a projection of the M_*_-{sigma} relation. When the velocity dispersion cannot be measured (at high z or low dispersions), the BH-size-mass relation should be used as a proxy for BH mass in favor of just galaxy or bulge mass.
124. Binary AGNs from the VLA Stripe 82 survey
ID:
ivo://CDS.VizieR/J/ApJ/799/72
Title:
Binary AGNs from the VLA Stripe 82 survey
Short Name:
J/ApJ/799/72
Date:
21 Oct 2021
Publisher:
CDS
Description:
Galaxy mergers play an important role in the growth of galaxies and their supermassive black holes. Simulations suggest that tidal interactions could enhance black hole accretion, which can be tested by the fraction of binary active galactic nuclei (AGNs) among galaxy mergers. However, determining the fraction requires a statistical sample of binaries. We have identified kiloparsec-scale binary AGNs directly from high-resolution radio imaging. Inside the 92deg^2^ covered by the high-resolution Very Large Array survey of the Sloan Digital Sky Survey (SDSS) Stripe 82 field, we identified 22 grade A and 30 grade B candidates of binary radio AGNs with angular separations less than 5" (10kpc at z=0.1). Eight of the candidates have optical spectra for both components from the SDSS spectroscopic surveys and our Keck program. Two grade B candidates are projected pairs, but the remaining six candidates are all compelling cases of binary AGNs based on either emission line ratios or the excess in radio power compared to the H{alpha}-traced star formation rate. Only two of the six binaries were previously discovered by an optical spectroscopic search. Based on these results, we estimate that ~60% of our binary candidates would be confirmed once we obtain complete spectroscopic information. We conclude that wide-area high-resolution radio surveys offer an efficient method to identify large samples of binary AGNs. These radio-selected binary AGNs complement binaries identified at other wavelengths and are useful for understanding the triggering mechanisms of black hole accretion.
125. Black hole mass and accretion rate of AGNs
ID:
ivo://CDS.VizieR/J/ApJ/614/91
Title:
Black hole mass and accretion rate of AGNs
Short Name:
J/ApJ/614/91
Date:
21 Oct 2021
Publisher:
CDS
Description:
Using an empirical relation between the broad-line region size and optical continuum luminosity, we estimated the black hole mass and accretion rate for 135 active galactic nuclei (AGNs) with double-peaked broad emission lines in two samples, one from the Sloan Digital Sky Survey (SDSS, Cat. <J/AJ/126/2579>) and the other from a survey of radio-loud broad emission line AGNs (Eracleous & Halpern, 2003, Cat. <J/ApJ/599/886>).
126. Black hole mass and velocity dispersion relation
ID:
ivo://CDS.VizieR/J/ApJ/641/L21
Title:
Black hole mass and velocity dispersion relation
Short Name:
J/ApJ/641/L21
Date:
21 Oct 2021
Publisher:
CDS
Description:
We examine whether active galaxies obey the same relation between black hole mass and stellar velocity dispersion as inactive systems, using the largest published sample of velocity dispersions for active nuclei to date. The combination of 56 original measurements with objects from the literature not only increases the sample from the 15 considered previously to 88 objects but allows us to cover an unprecedented range in both stellar velocity dispersion (30-268km/s) and black hole mass (10^5^-10^8.6^M_{sun}_).
127. Black hole masses in megamaser disk galaxies
ID:
ivo://CDS.VizieR/J/ApJ/826/L32
Title:
Black hole masses in megamaser disk galaxies
Short Name:
J/ApJ/826/L32
Date:
21 Oct 2021
Publisher:
CDS
Description:
We use new precision measurements of black hole (BH) masses from water megamaser disks to investigate scaling relations between macroscopic galaxy properties and supermassive BH mass. The megamaser-derived BH masses span 10^6^-10^8^M_{sun}_, while all the galaxy properties that we examine (including total stellar mass, central mass density, and central velocity dispersion) lie within a narrower range. Thus, no galaxy property correlates tightly with M_BH_ in ~L* spiral galaxies as traced by megamaser disks. Of them all, stellar velocity dispersion provides the tightest relation, but at fixed {sigma}_*_ the mean megamaser M_BH_ are offset by -0.6+/-0.1dex relative to early-type galaxies. Spiral galaxies with non-maser dynamical BH masses do not appear to show this offset. At low mass, we do not yet know the full distribution of BH mass at fixed galaxy property; the non-maser dynamical measurements may miss the low-mass end of the BH distribution due to an inability to resolve their spheres of influence and/or megamasers may preferentially occur in lower-mass BHs.
128. Black-hole masses of type-1 AGNs
ID:
ivo://CDS.VizieR/J/A+A/549/A119
Title:
Black-hole masses of type-1 AGNs
Short Name:
J/A+A/549/A119
Date:
21 Oct 2021
Publisher:
CDS
Description:
We derive masses of the central supermassive black hole (SMBH) and accretion rates for 154 type 1 AGN belonging to a well-defined X-ray-selected sample, the XMM-Newton serendipitous sample (XBS). We used the most recent "single-epoch" relations, based on H{beta] and MgII {lambda}2798{AA} emission lines, to derive the SMBH masses. We then used the bolometric luminosities, computed on the basis of an SED-fitting procedure, to calculate the accretion rates, both absolute and normalized to the Eddington luminosity (Eddington ratio).
129. Black hole masses of z~1.4 AGNs from SXDS
ID:
ivo://CDS.VizieR/J/ApJ/761/143
Title:
Black hole masses of z~1.4 AGNs from SXDS
Short Name:
J/ApJ/761/143
Date:
21 Oct 2021
Publisher:
CDS
Description:
In order to investigate the growth of supermassive black holes (SMBHs), we construct the black hole mass function (BHMF) and Eddington ratio distribution function (ERDF) of X-ray-selected broad-line active galactic nuclei (AGNs) at z~1.4 in the Subaru XMM-Newton Deep Survey (SXDS) field. A significant part of the accretion growth of SMBHs is thought to take place in this redshift range. Black hole masses of X-ray-selected broad-line AGNs are estimated using the width of the broad MgII line and 3000{AA} monochromatic luminosity. We supplement the MgII FWHM values with the H{alpha} FWHM obtained from our NIR spectroscopic survey. Using the black hole masses of broad-line AGNs at redshifts between 1.18 and 1.68, the binned broad-line AGN BHMFs and ERDFs are calculated using the V_max_ method. To properly account for selection effects that impact the binned estimates, we derive the corrected broad-line AGN BHMFs and ERDFs by applying the maximum likelihood method, assuming that the ERDF is constant regardless of the black hole mass. We do not correct for the non-negligible uncertainties in virial BH mass estimates. If we compare the corrected broad-line AGN BHMF with that in the local universe, then the corrected BHMF at z=1.4 has a higher number density above 10^8^M_{sun}_ but a lower number density below that mass range. The evolution may be indicative of a downsizing trend of accretion activity among the SMBH population. The evolution of broad-line AGN ERDFs from z=1.4 to 0 indicates that the fraction of broad-line AGNs with accretion rates close to the Eddington limit is higher at higher redshifts.
130. Black hole mass estimates
ID:
ivo://CDS.VizieR/J/ApJS/168/1
Title:
Black hole mass estimates
Short Name:
J/ApJS/168/1
Date:
21 Oct 2021
Publisher:
CDS
Description:
We describe the general problem of estimating black hole masses of active galactic nuclei (AGNs) by calculating the conditional probability distribution of M_BH_ given some set of observables. We estimated M_BH_ from both CIV and H{beta} for a sample of 100 sources, including new spectra of 29 quasars.