The X-Ray Power Spectral Density Function and Black Hole Mass Estimate for the Seyfert Active Galactic Nucleus IC 4329a
Abstract
We present the X-ray broadband power spectral density function (PSD) of the X-ray-luminous Seyfert IC 4329a, constructed from light curves obtained via Rossi X-ray Timing Explorer monitoring and an XMM-Newton observation. Modeling the 3-10 keV PSD using a broken power-law PSD shape, a break in power-law slope is significantly detected at a temporal frequency of 2.5+2.5 -1.7 × 10-6 Hz, which corresponds to a PSD break timescale T b of 4.6+10.1 -2.3 days. Using the relation between T b, black hole mass M BH, and bolometric luminosity as quantified by McHardy and coworkers, we infer a black hole mass estimate of M BH = 1.3+1.0 -0.3 × 108 M sun and an accretion rate relative to Eddington of 0.21+0.06 -0.10 for this source. Our estimate of M BH is consistent with other estimates, including that derived by the relation between M BH and stellar velocity dispersion. We also present PSDs for the 10-20 and 20-40 keV bands; they lack sufficient temporal frequency coverage to reveal a significant break, but are consistent with the same PSD shape and break frequency as in the 3-10 keV band.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- June 2009
- DOI:
- 10.1088/0004-637X/698/2/1740
- arXiv:
- arXiv:0905.0495
- Bibcode:
- 2009ApJ...698.1740M
- Keywords:
-
- galaxies: active;
- galaxies: individual: IC 4329a;
- galaxies: Seyfert;
- X-rays: galaxies;
- Astrophysics - High Energy Astrophysical Phenomena;
- Astrophysics - Galaxy Astrophysics
- E-Print:
- Accepted for publication in ApJ. 11 pages, 6 figures (5 color)