Oscillation Phenomena in the disk around the massive black hole Sagittarius A*
Abstract
We report the detection of radio QPOs with structure changes using the Very Long Baseline Array (VLBA) at 43 GHz. We found conspicuous patterned changes of the structure with P = 16.8 +- 1.4, 22.2 +- 1.4, 31.2 +- 1.5, 56.4 +- 6 min, very roughly in a 3:4:6:10 ratio. The first two periods show a rotating one-arm structure, while the P = 31.4 min shows a rotating 3-arm structure, as if viewed edge-on. At the central 50 microasec the P = 56.4 min period shows a double amplitude variation of those in its surroundings. Spatial distributions of the oscillation periods suggest that the disk of SgrA* is roughly edge-on, rotating around an axis with PA = -10 degree. Presumably, the observed VLBI images of SgrA* at 43 GHz retain several features of the black hole accretion disk of SgrA* in spite of being obscured and broadened by scattering of surrounding plasma.
Cite
@article{arxiv.0906.5511,
title = {Oscillation Phenomena in the disk around the massive black hole Sagittarius A*},
author = {M. Miyoshi and Zhi-Qiang Shen and T. Oyama and R. Takahashi and Y. Kato},
journal= {arXiv preprint arXiv:0906.5511},
year = {2016}
}
Comments
24 pages, 20 figures, revised version submitted to MN main journal (2010, Jan., 12th)