Long-term temporal variability of Cygnus X-2
Long-term temporal variability of Cygnus X-2
复制标题
Cygnus X-2 的长期时间变化
DOI：
10.1086/166376
复制
发表时间：
1988
期刊：
影响因子：
--
通讯作者：
S. Kahn
中科院分区：
文献类型：
--
作者：
S. Vrtilek;J. Swank;R. Kelley;S. Kahn
本文介绍了利用OSO 8、HEAO 1和Einstein上的仪器对低质量双星X射线源Cyg X-2进行的五年多的观测。在从几分钟到几天的时间尺度上，强度的不规则变化高达60%。该源似乎有长期的低光度状态，在此期间，持续约三天的下降发生。当这些长倾角发生时，它们总是出现在光学确定的9.8天轨道周期的同一相位。有三种不同类型的短期下降区分光谱硬度和强度之间的不同相关性。21篇参考文献。
Observations of the low-mass binary X-ray source Cyg X-2 taken over a five-year period using instruments on OSO 8, HEAO 1, and Einstein are presented. Irregular changes in intensity of up to 60 percent on time scales ranging from minutes to days are seen. The source appears to have long-term low-luminosity states during which dips lasting about three days occur. When these long dips occur, they always appear at the same phase in the optically determined 9.8-day orbital period. There are three distinct types of short-term dips distinguished by differing correlations between spectral hardness and intensity. 21 references.