other query
modes : |
Identifier query |
Coordinate query |
Criteria query |
Reference query |
Basic query |
Script submission |
TAP |
Output options |
Help |

**
2007ApJS..168....1K -
**
*
Astrophys. J., Suppl. Ser., 168, 1-18 (2007/January-0)
*

* *

**
Virial masses of black holes from single epoch spectra of active galactic nuclei.
**

*
KELLY B.C. and BECHTOLD J.
*

**
Abstract (from CDS):
**

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. Special attention is given to the case where one uses the AGN continuum luminosity and emission line widths to estimate M_{BH}, and we outline how to set up the conditional probability distribution of M_{BH}given the observed luminosity, line width, and redshift. We show how to combine the broad-line estimates of M_{BH}with information from an intrinsic correlation between M_{BH}and *L*, and from the intrinsic distribution of M_{BH}, in a manner that improves the estimates of M_{BH}. Simulation was used to assess how the distribution of M_{BH}inferred from the broad-line mass estimates differs from the intrinsic distribution, and we find that this can lead to an inferred distribution that is too broad. We use these results and a sample of 25 sources that have recent reverberation mapping estimates of AGN black hole masses to investigate the effectiveness of using the C IV emission line to estimate M_{BH}and to indirectly probe the C IV region size-luminosity (*R*-*L*) relationship. A linear regression of logL_{λ}(1549 Å) on logM_{BH}found that L_{1549}∝M^{1.17±0.22}_{BH}. A linear regression also found that M_{BH}∝L^{0.41±0.07}_{1549}FWHM^{2}_CIV_, implying a C IV *R*-*L* relationship of the form R_CIV_{∝L}0.41±0.07^_{1549}. Including the C IV line FWHM resulted in a reduction of a factor of ∼1/3 in the error in the estimates of M_{BH}over simply using the continuum luminosity, statistically justifying its use. We estimated M_{BH}from both C IV and Hβ for a sample of 100 sources, including new spectra of 29 quasars. We find that the two emission lines give consistent estimates if one assumes R∝L^{1/2}_{UV} for both lines.

**
Abstract Copyright:
**
∼

**
Journal keyword(s):
**
*
Galaxies: Active - Line: Profiles - Methods: Data Analysis - Methods: Statistical - Galaxies: Quasars: Emission Lines
*

**
VizieR on-line data:
**
<Available at CDS (J/ApJS/168/1): table5.dat>

**
Nomenclature:
**
Table 5: [KB2007] JHHMMSS.s+DDMMSS.s N=100.

**
Simbad objects:
**
125

To bookmark this query, right click on this link: simbad:2007ApJS..168....1K and select 'bookmark this link' or equivalent in the popup menu

2021.05.17-04:13:19

© Université de Strasbourg/CNRS

• Contact