论文标题
GSN 069中重复潮汐破坏：长期演变和准周期喷发模型的限制
Repeating tidal disruptions in GSN 069: Long-term evolution and constraints on quasi-periodic eruptions' models
论文作者
论文摘要
GSN 069是已经鉴定出准周期性喷发（QPE）的第一个银河核。这些是高振幅，每〜9小时，持续约1小时，软X射线突发爆发，X射线计数速率相对于原本稳定的静态水平，X射线计数速率最多增加了两个数量级。 X射线光谱特性和GSN 069在最初几年的长期演变与长期寿命的潮汐破坏事件（TDE）一致。在这里，我们通过研究了11 xmm-Newton的时机和光谱X射线数据，从11 Xmm-Newton，一个Chandra，一个Chandra和34个迅速观察到从分钟数到几分钟的时间表，从11 xmm-Newton，1个Chandra和34个迅速观察到GSN 069中的长期X射线演化的性质。 GSN 069中的QPE是一种瞬时现象，其寿命> 1.05年。 QPE强度和复发时间振荡，并允许定义强弱QPE和长短复发时间。在用QPE的观察结果中，静态水平表现出准周期性振荡，其周期等于连续QPE之间的平均分离。 QPE光谱演化与非常紧凑的区域的热发射一致，该区域快速加热并随后通过X射线发射冷却，同时膨胀了大约3倍。静态水平的长期演变的特征是两个重复的TDE相距约9年。我们在第二个TDE之前检测到前体X射线耀斑，该耀斑可能与圆盘形成过程中的圆形化相有关。在第一个TDE之前，暂时检测到类似的前体耀斑。 GSN 069对未来的X射线观察有望限制QPE来源以及QPE与重复TDE之间的关系受到限制，这对已识别QPE的其他来源产生了影响。 [简略]
GSN 069 is the first galactic nucleus where quasi-periodic eruptions (QPEs) have been identified. These are high-amplitude, soft X-ray bursts recurring every ~9 hr, lasting ~1 hr, and during which the X-ray count rate increases by up to two orders of magnitude with respect to an otherwise stable quiescent level. The X-ray spectral properties and the long-term evolution of GSN 069 in the first few years are consistent with a long-lived tidal disruption event (TDE). Here we derive the properties of QPEs and of the long-term X-ray evolution in GSN 069 over the past 12 yr by studying timing and spectral X-ray data from 11 XMM-Newton, one Chandra, and 34 Swift observations on timescales ranging from minutes to years. QPEs in GSN 069 are a transient phenomenon with a lifetime > 1.05 yr. The QPE intensity and recurrence time oscillate and allow for alternating strong-weak QPEs and long-short recurrence times to be defined. In observations with QPEs, the quiescent level exhibits a quasi-periodic oscillation with a period equal to the average separation between consecutive QPEs. The QPE spectral evolution is consistent with thermal emission from a very compact region that heats up quickly and subsequently cools down via X-ray emission while expanding by a factor of ~3 in radius. The long-term evolution of the quiescent level is characterised by two repeating TDEs ~9 yr apart. We detect a precursor X-ray flare prior to the second TDE that may be associated with the circularisation phase during disc formation. A similar precursor flare is tentatively detected just before the first TDE. Future X-ray observations of GSN 069 promise that the QPE origin and the relation between QPEs and repeating TDEs in this galactic nucleus will be constrained, with consequences for the other sources where QPEs have been identified. [abridged]
