Peculiar Physical Properties of HST-1 in M87

Journal of astrophysics and astronomy

Y. J. Chen1¹  G.-Y. Zhao¹  Z.-Q. Shen¹ 

[1] Key Laboratory for Research in Galaxies and Cosmology, Shanghai Astronomical Observatory, Chinese Academy of Sciences, 80 Nandan Road, Shanghai 200030, China.$$

关键词: Polarization;    galaxies: active;    galaxies: individual (M87);    galaxies: jets;    radio continuum: galaxies.;   

DOI  :  

学科分类：天文学(综合)

来源: Indian Academy of Sciences

【 摘 要 】

We report on VLA observations of HST-1 in M87 at 8 GHz from 2003–2007, during which a long major outburst occurs from radio to X-ray wave bands. At the VLA resolution, the flux density of HST-1 rises rapidly from 2003, peaks at the end of 2004, and then falls slowly in subsequent stages, which is similar to that in optical and X-ray wave bands. It appears that HST-1 moves with an apparent speed of 1.23𝑐 ± 0.91𝑐, and the fractional polarization keeps rising through the whole major outburst. The persistent increase in polarization level may mainly be attributed to the formation of a couple of new `subcomponents’ of relatively high degree of polarization within HST-1, and the weakening depolarization due to Faraday rotation and/or opacity through the whole major outburst.

【 授权许可】

Unknown