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arXiv 2104.14580astro-ph.HE
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潮汐中断事件

Tidal Disruption Events

Suvi Gezari

摘要:

恒星被潮汐撕裂并被潜伏在星系中心的大质量黑洞(MBH)吞噬的概念在20世纪70年代末首次吸引了理论家。这些罕见的,但启发性的现象,探测其他休眠MBH的观测证据,首先出现在档案搜索的软X射线ROSAT全天巡天在20世纪90年代,但最近加速增加调查功率在光时域,潮汐破裂事件(TDEs)现在被视为一类光学核瞬变与独特的光谱特征。多波长观测的TDEs揭示了全色发射,探测范围广泛的尺度,从最里面的区域的吸积流,周围的环核介质。我回顾了目前的普查报告中的56个TDEs的文献中,他们观察到的属性可以概括如下:$\bullet$的光学光变曲线遵循幂律下降从峰值尺度与推断的中央黑洞质量预期的回落率的恒星碎片,但上升时间没有。$\bullet$紫外/光学和软X射线热辐射来自不同的空间尺度,它们的强度比具有很大的动态范围,并且是高度可变的,这为这两个组件的动力提供了重要的线索。$\bullet$它们可以分为三个光谱类别,与Bowen荧光线发射显示出一个更热,更紧凑的线发射区域的偏好,而那些只有He II发射线是最罕见的类。

英文摘要:

The concept of stars being tidally ripped apart and consumed by a massive black hole (MBH) lurking in the center of a galaxy first captivated theorists in the late 1970's. The observational evidence for these rare but illuminating phenomena for probing otherwise dormant MBHs, first emerged in archival searches of the soft X-ray ROSAT All-Sky Survey in the 1990's; but has recently accelerated with the increasing survey power in the optical time domain, with tidal disruption events (TDEs) now regarded as a class of optical nuclear transients with distinct spectroscopic features. Multiwavelength observations of TDEs have revealed panchromatic emission, probing a wide range of scales, from the innermost regions of the accretion flow, to the surrounding circumnuclear medium. I review the current census of 56 TDEs reported in the literature, and their observed properties can be summarized as follows: $\bullet$ The optical light curves follow a power-law decline from peak that scales with the inferred central black hole mass as expected for the fallback rate of the stellar debris, but the rise time does not. $\bullet$ The UV/optical and soft X-ray thermal emission come from different spatial scales, and their intensity ratio has a large dynamic range, and is highly variable, providing important clues as to what is powering the two components. $\bullet$ They can be grouped into three spectral classes, and those with Bowen fluorescence line emission show a preference for a hotter and more compact line-emitting region, while those with only He II emission lines are the rarest class.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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