Active galactic nucleus black hole mass estimates in the era of time domain astronomy
- Department of Physics, Broida Hall, University of California, Santa Barbara, CA 93106-9530 (United States)
- Department of Astronomy, 430 Portola Plaza, Box 951547, University of California, Los Angeles, CA 90095-1547 (United States)
- Department of Physics and Astronomy, Seoul National University, Seoul 151-742 (Korea, Republic of)
We investigate the dependence of the normalization of the high-frequency part of the X-ray and optical power spectral densities (PSDs) on black hole mass for a sample of 39 active galactic nuclei (AGNs) with black hole masses estimated from reverberation mapping or dynamical modeling. We obtained new Swift observations of PG 1426+015, which has the largest estimated black hole mass of the AGNs in our sample. We develop a novel statistical method to estimate the PSD from a light curve of photon counts with arbitrary sampling, eliminating the need to bin a light curve to achieve Gaussian statistics, and we use this technique to estimate the X-ray variability parameters for the faint AGNs in our sample. We find that the normalization of the high-frequency X-ray PSD is inversely proportional to black hole mass. We discuss how to use this scaling relationship to obtain black hole mass estimates from the short timescale X-ray variability amplitude with precision ∼0.38 dex. The amplitude of optical variability on timescales of days is also anticorrelated with black hole mass, but with larger scatter. Instead, the optical variability amplitude exhibits the strongest anticorrelation with luminosity. We conclude with a discussion of the implications of our results for estimating black hole mass from the amplitude of AGN variability.
- OSTI ID:
- 22348401
- Journal Information:
- Astrophysical Journal, Vol. 779, Issue 2; Other Information: Country of input: International Atomic Energy Agency (IAEA); ISSN 0004-637X
- Country of Publication:
- United States
- Language:
- English
Similar Records
The Kepler Light Curves of AGN: A Detailed Analysis
A SOFT X-RAY REVERBERATION LAG IN THE AGN ESO 113-G010