Multiresonance orbital model of HF QPOs
Abstract
Using known frequencies of the twin peak highfrequency quasiperiodic oscillations (HF QPOs) and known mass M of the central black hole, the blackhole dimensionless spin a can be determined assuming a concrete version of the resonance model. However, large range of observationally limited values of the black hole mass implies a low precision of the spin estimates. We discuss the possibility of higher precision of the black hole spin a measurements in the framework of multiresonance model inspired by observations of more than two HF QPOs in some black hole sources. We determine the spin and mass dependence of the twin peak frequencies with a general rational ratio n:m assuming a nonlinear resonance of oscillations with the epicyclic and Keplerian frequencies or their combinations. In the multiresonant model, the twin peak resonances are combined properly to give the observed frequency set. We focus on the special case of duplex frequencies, when the top, bottom, or mixed frequency is common at two different radii where the resonances occur giving triple frequency sets.
 Publication:

Feeding Compact Objects: Accretion on All Scales
 Pub Date:
 February 2013
 DOI:
 10.1017/S1743921312020182
 arXiv:
 arXiv:1212.6668
 Bibcode:
 2013IAUS..290..315S
 Keywords:

 accretion;
 accretion disks;
 Xrays: binaries;
 black hole physics;
 Astrophysics  High Energy Astrophysical Phenomena
 EPrint:
 2 pages, to be published in Proceedings of IAUS 290 "Feeding Compact Objects: Accretion on All Scales", C. M. Zhang, T. Belloni, M. Mendez and S. N. Zhang (eds.)