相关论文: Black hole mass estimation from X-ray variability …
Recent studies of active galactic nuclei (AGN) found a statistical inverse linear scaling between the X-ray normalized excess variance $\sigma_{\rm rms}^2$ (variability amplitude) and the black hole mass spanning over $M_{\rm BH}=10^6-…
Our objective is to critically assess the X-ray flux variability as a tool for measuring the black hole (BH) mass in active galactic nuclei (AGN). We aim to establish a prescription for estimating BH masses based on measurements of the…
Values of black hole masses are frequently determined with the help of the reverberation method. This method requires a specific geometrical factor related to the distribution of the orbits of the Broad Line Region clouds. Onken et al.…
Several investigations of the X-ray variability of active galactic nuclei (AGN) using the normalised excess variance (${\sigma^2_{\rm NXS}}$) parameter have shown that variability has a strong anti-correlation with black hole mass ($M_{\rm…
Aims. Both the black hole mass and the X-ray luminosity of AGNs have been found to be anti-correlated with the normalized excess variance ($\sigma_{\rm rms}^2 $) of the X-ray light curves. We investigate which correlation with $\sigma_{\rm…
We calibrate reverberation-based black hole masses in active galactic nuclei (AGNs) by using the correlation between black hole mass, M, and bulge/spheroid stellar velocity dispersion, sigma. We use new measurements of sigma for 6 AGNs and…
Reverberation mapping methods have been used to measure masses in about three dozen AGNs. The consistency of the virial masses computed from line widths and time delays, the relationship between black hole mass and host-galaxy stellar bulge…
We discuss two methods to estimate black hole (BH) masses using X-ray data only: from the X-ray variability amplitude and from the photon index Gamma. The first method is based on the anti-correlation between BH mass and X-ray variability…
Estimating the black hole mass at the center of galaxies is a fundamental step not only for understanding the physics of accretion, but also for the cosmological evolution of galaxies. Recently a new method, based solely on X-ray data, was…
The determination of the central black hole mass is crucial to the understanding of AGN physics. In this paper we briefly review some methods that are currently used to estimate the black hole mass of AGNs. Particularly we demonstrate the…
We test a novel method for estimating black hole masses ($M_{\rm BH}$) in obscured active galactic nuclei (AGN) that uses proxies to measure the full-width half maximum of broad H$\alpha$ (FWHM$_{\rm bH\alpha}$) and the accretion disk…
A new empirical formulae is given for estimating the masses of black holes in AGNs from the H beta velocity dispersion and the continuum luminosity at 5100 Angstroms. It is calibrated to reverberation-mapping and stellar-dynamical estimates…
The masses of supermassive black holes in broad-line active galactic nuclei (AGNs) can be measured through reverberation mapping, but this method currently cannot be applied to very large samples or to high-redshift AGNs. As a practical…
Determining the black hole masses in active galactic nuclei (AGN) is of crucial importance to constrain the basic characteristics of their central engines and shed light on their growth and co-evolution with their host galaxies. While the…
We investigate the dependence of the normalization of the high-frequency part of the X-ray and optical power spectral densities (PSD) on black hole mass for a sample of 39 active galactic nuclei (AGN) with black hole masses estimated from…
A simple refinement is proposed to the Dibai method for determining black hole masses in type-1 thermal AGNs. Comparisons with reverberation mapping black hole masses and host galaxy bulge properties suggest that the method is accurate to…
The relation between the 2-10 keV, long term, excess variance and AGN black hole mass is considered in this work. A significant anti-correlation is found between these two quantities in the sense that the excess variance decreases with…
In the era of massive photometric surveys, we explore several approaches to estimate the masses of supermassive black holes (SMBHs) in active galactic nuclei (AGN) from optical ground-based imaging, in each case comparing to the independent…
The goal of this project is to construct an estimator for the masses of supermassive black holes in active galactic nuclei (AGNs) based on the broad Halpha emission line. We make use of published reverberation mapping data. We remeasure all…
In a recent work we demonstrated that a novel X-ray scaling method, originally introduced for Galactic black holes (GBHs), can be reliably extended to estimate the mass of supermassive black holes accreting at a moderate to high level. Here…