The Importance of Discovering a 3:2 Twin-Peak Quasi-periodic Oscillation in an Ultraluminous X-Ray Source, or How to Solve the Puzzle of Intermediate-Mass Black Holes
Abstract
Recently, twin-peak quasi-periodic oscillations (QPOs) have been observed in a 3:2 ratio for three Galactic black hole microquasars with frequencies that have been shown to scale as 1/M, as expected for general relativisitic motion near a black hole. It may be possible to extend this result to distinguish between the following two disparate models that have been proposed for the puzzling ultraluminous X-ray sources (ULXs): (1) an intermediate-mass black hole (M~103 Msolar) radiating very near the Eddington limit and (2) a conventional black hole (M~10 Msolar) accreting at a highly super-Eddington rate with its emission beamed along the rotation axis. We suggest that one could discriminate between these models by detecting the counterpart of a Galactic twin-peak QPO in a ULX: the expected frequency for the intermediate-mass black hole model is only about 1 Hz, whereas for the conventional black hole model the expected frequency would be the ~100 Hz value observed for the Galactic microquasars.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- July 2004
- DOI:
- 10.1086/422810
- arXiv:
- arXiv:astro-ph/0402012
- Bibcode:
- 2004ApJ...609L..63A
- Keywords:
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- Accretion;
- Accretion Disks;
- Black Hole Physics;
- Galaxies: Quasars: General;
- Relativity;
- X-Rays: Galaxies;
- X-Rays: General;
- Astrophysics
- E-Print:
- 3 p., 2 figs