Flaring X-ray emission from HST-1, a knot in the M87 jet

被引：98

作者：

Harris, DE

Biretta, JA

Junor, W

Perlman, ES

Sparks, WB

Wilson, AS

机构：

[1] Harvard Smithsonian Ctr Astrophys, Smithsonian Astrophys Observ, Cambridge, MA 02138 USA

[2] Space Telescope Sci Inst, Baltimore, MD 21218 USA

[3] Los Alamos Natl Lab, Los Alamos, NM 87545 USA

[4] Univ Maryland, Joint Ctr Astrophys, Baltimore, MD 21250 USA

[5] Univ Maryland, Dept Astron, College Pk, MD 20742 USA

来源：

ASTROPHYSICAL JOURNAL | 2003年 / 586卷 / 01期

基金：

美国国家科学基金会; 美国国家航空航天局;

关键词：

galaxies : active; galaxies : individual (M87); galaxies : jets; magnetic fields; radiation mechanisms : nonthermal;

D O I：

10.1086/374773

中图分类号：

P1 [天文学];

学科分类号：

0704 ;

摘要：

We present Chandra X-ray monitoring of the M87 jet in 2002, which shows that the intensity of HST-1, an optical knot 0."8 from the core, increased by a factor of 2 in 116 days and a factor of 4 in 2 yr. There was also a significant flux decrease over 2 months, with suggestive evidence for a softening of the spectrum. From this variability behavior, we argue that the bulk of the X-ray emission of HST-1 comes from synchrotron emission. None of the other conceivable emission processes can match the range of observed characteristics. By estimating synchrotron model parameters for various bulk relativistic velocities, we demonstrate that a model with a Doppler factor delta in the range 2-5 fits our preliminary estimates of light-travel time and synchrotron loss timescales.

引用

页码：L41 / L44

页数：4

共 15 条

[1] DETECTION OF PROPER MOTIONS IN THE M87 JET [J].