论文标题
Black Hole Transient Swift J1658.2-4242的极端触发器状态过渡中的一个基础时钟
An underlying clock in the extreme flip-flop state transitions of the black hole transient Swift J1658.2-4242
论文作者
论文摘要
目的：触发器是顶级X射线通量变化，在某些瞬态积聚的黑洞二元系统中发生，并具有光谱硬度和功率密度光谱（PDS）的同时变化。当这些系统的演变中，当增生磁盘发射开始占主导地位时，它们发生在这些系统的演变中。人字拖很少观察到，并且知之甚少。 方法：我们在2018年Swift J1658.2-4242的爆发中检测到15个触发器，在XMM-Newton，Nustar，Astrosat，Swift，Swift，Insight-HXMT，Integne，Integne和ATCA的观察中。我们分析了他们的光曲线，寻找周期性，计算其PD并适合其X射线光谱，以调查触发器转换过程中的源行为，以及具有触发器的间隔与其他爆发的间隔有何不同。 结果：Swift J1658.2-4242的触发器的触发率极为多样，在〜100左右的通量差异高达77％，比到目前为止所看到的要大得多。我们观察到PDS与急剧变化的PDS的根本变化，其特征是Casi周期振荡型C和A之间的过渡，而A和A从未观察到。 PD的变化延迟，但比光曲线的变化更快。触发器以两个间隔发生，分别为两个星期，没有看到这些现象。两个触发器状态之间的过渡发生在基本周期的随机整数倍数上，第一个间隔为2.761K，第二个间隔为2.61k。光谱分析表明，高和低通量触发器状态相似，但与缺少触发器的间隔不同。积聚盘的内部温度的变化是触发触发器中大多数通量差异的原因。我们强调了纠正粉尘散射光环对X射线光谱的影响的重要性。
Aims: Flip-flops are top-hat-like X-ray flux variations which occur in some transient accreting black hole binary systems and feature simultaneous changes in the spectral hardness and the Power Density Spectrum (PDS). They occur at a crucial time in the evolution of these systems, when the accretion disk emission starts to dominate over coronal emission. Flip-flops have only rarely been observed and are poorly understood. Methods: We detect 15 flip-flops in the 2018 outburst of Swift J1658.2-4242, in observations by XMM-Newton, NuSTAR, Astrosat, Swift, Insight-HXMT, INTEGRAL, and ATCA. We analyse their light curves, search for periodicities, compute their PDS, and fit their X-ray spectra, to investigate the source behaviour during flip-flop transitions, and how the interval featuring flip-flops differs from the rest of the outburst. Results: The flip-flops of Swift J1658.2-4242 are of an extreme variety, exhibiting flux differences of up to 77% within ~100s, much larger than has been seen so far. We observe radical changes in the PDS simultaneous with the sharp flux variations, featuring transitions between the Quasi-Periodic Oscillation types C and A, which have never been observed before. Changes to the PDS are delayed, but more rapid than changes in the light curve. Flip-flops occur in two intervals, separated by two weeks in which these phenomena were not seen. Transitions between the two flip-flop states occurred at random integer multiples of a fundamental period, of 2.761ks in the first interval, and 2.61ks in the second. Spectral analysis reveals the high and low flux flip-flop states to be similar, but distinct from intervals lacking flip-flops. A change in the inner temperature of the accretion disk is responsible for most of the flux difference in the flip-flops. We highlight the importance of correcting for the influence of the dust scattering halo on the X-ray spectra.
