标题： 1998年爆发期间4U 1630-47的时间演化特性 显示英文标题

标题： The Timing Evolution of 4U 1630-47 During its 1998 Outburst

摘要： 我们报告了利用 Rossi X 射线时变探测器（RXTE）获得的数据，研究 1998 年 4U1630-47 星爆发期间的计时演化情况。计数率以及在硬度-强度、颜色-颜色图中的位置，以及简单的谱拟合被用来追踪同时发生的光谱变化。 该源展示了七种不同的计时行为类型，其中大多数与经典的黑洞光谱/计时状态存在差异。 与以往的爆发形成鲜明对比的是，我们在爆发的几乎所有阶段都发现了准周期振荡（QPO）信号，频率范围在 0.06Hz 到 14Hz，并且具有多种显著的特征。 特别是，我们在早期上升阶段发现了幅度较大的 QPO（高达 23% rms）。随后，在光曲线中占主导地位的是缓慢的 0.1Hz 半规则短时（约 5 秒）、深度约为 9% 到 16% 的下降现象。 此时存在两个 QPO，其中一个稳定在接近 13.5Hz，另一个的频率在下降过程中从 6-8Hz 降至约 4.5Hz。 BeppoSAX 在非常晚期下降阶段的观测显示 4U1630-47 处于低态。 显示英文摘要

摘要： We report on the evolution of the timing of 4U1630-47 during its 1998 outburst using data obtained with the Rossi X-ray Timing Explorer (RXTE). The count rate and position in hardness-intensity, color-color diagrams and simple spectral fits are used to track the concurrent spectral changes. The source showed seven distinct types of timing behavior, most of which show differences with the canonical black hole spectral/timing states. In marked contrast to previous outbursts, we find quasi-periodic oscillation (QPO) signals during nearly all stages of the outburst with frequencies between 0.06Hz and 14Hz and a remarkable variety of other characteristics. In particular we find large (up to 23% rms) amplitude QPO on the early rise. Later, slow 0.1Hz semi- regular short (~ 5 sec), 9 to 16% deep dips dominate the light curve. At this time there are two QPOs, one stable near 13.5Hz and the other whose frequency drops from 6--8Hz to ~4.5 Hz during the dips. BeppoSAX observations during the very late declining phase show 4U1630-47 in a low state.