Faint hard X-ray sources in the Galactic Center region: Supernova ejecta fragments population

被引:19
作者
Bykov, AM [1 ]
机构
[1] AF Ioffe Phys Tech Inst, St Petersburg 194021, Russia
来源
ASTRONOMY & ASTROPHYSICS | 2003年 / 410卷 / 02期
关键词
acceleration of particles; radiation mechanisms : non-thermal; ISM; clouds; ISM : individual object : Galactic Center; ISM : supernova remnants; X-rays : diffuse background; EMISSION; REMNANT; CHANDRA; ORIGIN; CLOUDS;
D O I
10.1051/0004-6361:20031355
中图分类号
P1 [天文学];
学科分类号
0704 ;
摘要
Long Chandra observations of 17' x 17' field in the Galactic Center ( GC) region reported by Muno et al. (2003) have revealed a population of about 2000 hard faint X-ray sources limited by luminosities L-x greater than or equal to 10(31) erg s(-1). We show that fast moving knots (FMKs) of supernovae ejecta could comprise a sizeable fraction of the sources. Each supernova event can produce hundreds of FMKs. The presence of similar to3 supernova remnants of age similar to10(3) years in the GC region could provide the required number of the FMKs. Simulated X-ray spectra of the FMKs contain both thermal and nonthermal components. The nonthermal spectra are power-laws with hard photon indexes 0 less than or equal to Gamma less than or equal to 1.5 and prominent lines of some metals (e.g. Fe). The log N-log S distribution and the hardness ratios of the FMKs in the GC region are consistent with the Chandra findings. Spatial distribution of the FMKs in the GC region should appear as an ensemble of coherent shell and jet-like structures of a few arcmin-scale.
引用
收藏
页码:L5 / L8
页数:4
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