2013/10/07 by Andrea Kotrlova, Zdenek Stuchlik, Gabriel Torok
Physics and Astronomy · #astro-ph.HE
published as Acta Astronomica (2013) 63, 275 · 19 pages, 1 figure. arXiv admin note: substantial text overlap with arXiv:1305.3552
arxiv created 2013/10/07 · arxiv updated 2013/10/08
The multi-resonance orbital model of high-frequency quasi-periodic oscillations (HF QPOs) enables precise determination of the black hole dimensionless spin a if observed set of oscillations demonstrates three (or more) commensurable frequencies. The black hole spin is related to the frequency ratio only, while its mass M is related to the frequency magnitude. The model is applied to the triple frequency set of HF QPOs observed in Sgr A* source with frequency ratio 3:2:1. Acceptable versions of the multi-resonance model are determined by the restrictions on the Sgr A* supermassive black hole mass. Among the best candidates the version of strong resonances related to the black hole "magic" spin a=0.983 belongs. However, the version demonstrating the best agreement with the mass restrictions predicts spin a=0.980.