标题： RXTE/ASM对赫尔X-1的35天周期观测 显示英文标题

标题： RXTE/ASM Observations of the 35-day Cycle of Her X-1

摘要： 她的X-1自1996年2月起一直由RXTE上的ASM几乎连续地在软X射线（2-12 keV）范围内进行监测。 我们呈现了这些观测的分析，其中包括23个连续的35天周期。 我们呈现了对Her X-1的最佳35天周期光变曲线。 35天光变曲线中的特征如掩食和吸收凹陷，以及主高态和短高态交替出现的情况，都得到了很好的测量。 在低态期间X射线掩食的发生得到了确认，同时主高态的存在也得到了确认， 这些主高态在轨道相位0.23和0.68处突然开启。 主高态覆盖35天相位0-0.31，而短高态覆盖相位0.57-0.79，其中相位0由主高态开启定义。 我们发现短高态有延长的进入和退出阶段。 在主高态期间，行进的预掩食吸收凹陷逐渐变浅。 如果可以将行进的凹陷从主高态外推到短高态，则行进的预掩食凹陷周期最好通过重新分析档案数据确定为1.651 +/- 0.002天，或者仅使用单个主高态内的凹陷，则为1.646 +/- 0.003天。 显示英文摘要

摘要： Her X-1 has been monitored nearly continuously in soft X-rays (2-12 keV) since February 1996 by the ASM on board RXTE. We present analysis of these observations which include 23 contiguous 35-day cycles. We present the best yet average 35-day cycle lightcurve for Her X-1. 35-day lightcurve features such as eclipses and absorption dips, and the alternating occurrence of the Main High and Short High states, are well measured. The occurrence of X-ray eclipse during the Low state is confirmed as is the presence of Main High states that ``turn-on'' sharply at orbital phases 0.23 and 0.68. The Main High state covers 35-day phase 0-0.31 and the Short High state covers phase 0.57-0.79, with phase 0 defined by Main High state turn-on. We find extended ingresses and egresses for the Short High state. Marching pre-eclipse absorption dips progressively become shallower during the Main High state. The marching pre-eclipse dip period is best determined from reanalysis of archival data as 1.651 +/- .002 days if the dip marching can be extrapolated from the Main High state into the Short High state or 1.646 +/- .003 using dips within single Main High states alone.