ASCA对银河星团硬X射线源GRS 1758--258的观测
天体物理学
2009-10-28 v1
摘要
GRS 1758-258是银河中少数持久的硬X射线发射器(E>100 keV)之一。使用ASCA卫星,我们获得了GRS 1758-258在1-10 keV范围内的第一批详细数据,此前的观测受到与邻近强源GX5-1相关的混合问题的影响。该谱系由伸缩定律描述,其光子指数为1.7,且无强Fe发射线。如ROSAT在硬X射线flux处于较低强度状态时所观察到的显著软过量,未被检测到。然而,软成分的存在(最多占0.1-300 keV flux的5%)cannot被排除。对星际吸收(N_H=(1.5+-0.1) x 10^22 cm -2)的精确测量对应于光学消光,其显著排除了大质量伴星的存在。
关键词
引用
@article{arxiv.astro-ph/9609056,
title = {ASCA observations of the galactic bulge hard x-ray source GRS 1758--258},
author = {S. Mereghetti and D. I. Cremonesi and F. Haardt and T. Murakami and T. Belloni and A. Goldwurm},
journal= {arXiv preprint arXiv:astro-ph/9609056},
year = {2009}
}
备注
7 pages, AAS latex [11pt,aaspptwo,flushrt,tighten], + 1.ps figure Accepted for pubblication in ApJ, 09 02 96 Also available at http://fy.chalmers.se/~haardt/personal/curr.html Figures 1 and 2 available upon request at [email protected]