BeppoSAX observations of the Her X-1 short-on and anomalous low-states

被引：0

作者：

Parmar, AN ^{[1
]}

Oosterbroek, T ^{[1
]}

Dal Fiume, D ^{[1
]}

Orlandini, M ^{[1
]}

Santangelo, A ^{[1
]}

Del Sordo, S ^{[1
]}

Segreto, A ^{[1
]}

机构：

[1] ESA, Dept Space Sci, Div Astrophys, Noordwijk, Netherlands

来源：

X-RAY ASTRONOMY: STELLAR ENDPOINTS, AGN, AND THE DIFFUSE X-RAY BACKGROUND | 2001年 / 599卷

关键词：

accretion; accretion disks; stars : individual : Hercules X-1; stars : neutron;

D O I：

暂无

中图分类号：

P1 [天文学];

学科分类号：

0704 ;

摘要：

BeppoSAX recently observed the short-on and anomalous low-states of Her X-1. During the short-on state there are long intervals where the N-H is >5 x 10(22) atom cm(-2). These intervals become longer and occur similar to0.3 day earlier during each orbital cycle as the short-on state progresses. During intervals of high absorption the 0.1 keV blackbody is clearly detected. This implies the presence of separate scattering and absorbing components, or partial covering. Using BeppoSAX and RXTE data we discovered low-amplitude pulsations during the anomalous low-state of Her X-1 in 1999 July. The pulse period indicates that the Her X-1 underwent substantial spin-down close to the start of the anomalous low-state.

引用

页码：838 / 841

页数：2

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