Weighing the black holes in ultraluminous X-ray sources through timing
Astrophysics
2009-11-13 v1
Abstract
We describe a new method to estimate the mass of black holes in Ultraluminous X-ray Sources (ULXs). The method is based on the recently discovered ``variability plane'', populated by Galactic stellar-mass black-hole candidates (BHCs) and supermassive active galactic nuclei (AGNs), in the parameter space defined by the black-hole mass, accretion rate and characteristic frequency. We apply this method to the two ULXs from which low-frequency quasi-periodic oscillations have been discovered, M82 X-1 and NGC 5408 X-1. For both sources we obtain a black-hole mass in the range 100~1300 Msun, thus providing evidence for these two sources to host an intermediate-mass black hole.
Keywords
Cite
@article{arxiv.0804.3378,
title = {Weighing the black holes in ultraluminous X-ray sources through timing},
author = {P. Casella and G. Ponti and A. Patruno and T. Belloni and G. Miniutti and L. Zampieri},
journal= {arXiv preprint arXiv:0804.3378},
year = {2009}
}
Comments
5 pages, 2 figures, Accepted by MNRAS