AI 中文总结
研究潮汐瓦解事件中高光度相对论性喷流磁通量的起源，探讨恒星磁场、套索机制、吸积盘内磁通量三个候选源，发现吸积盘中黑洞附近预先存在的磁通量是最有可能驱动喷流的来源。
AI 中文摘要
潮汐瓦解事件（TDEs）发生在恒星靠近黑洞被潮汐力撕裂后，恒星碎片开始绕黑洞轨道运行。过去十年已发现数百个TDEs，预计未来调查会发现更多。一小部分此类事件会发射瞬态、高光度相对论性喷流。通常用布兰德福德-日纳杰克机制来解释，这意味着黑洞视界附近存在大量磁通量。问题是这种磁通量的起源是什么？本文研究了三个候选源：恒星磁场、黑洞周围大半径处的磁通量（套索机制）以及预先存在的吸积盘内部储存的磁通量。我们发现：观测到的恒星磁场不足以驱动这些喷流；套索机制需要浅径向磁场分布以及在黑洞附近捕获碎片带来的磁通量的机制；吸积盘中黑洞附近预先存在的磁通量是最合理的来源。
英文摘要
Tidal Disruption Events (TDEs) occur when a star approaches a black hole closely enough to be torn apart by tidal forces, after which the stellar debris begins to orbit the black hole. Over the past decade, hundreds of TDEs have been identified, with many more expected from upcoming surveys. A small subset of these events launch transient, highly luminous relativistic jets (10^47-10^48 erg/s isotropic-equivalent). These are generally interpreted in terms of the Blandford--Znajek mechanism, implying the presence of substantial magnetic flux near the black hole horizon. The question arises: What is the origin of this flux? In this paper, we investigate three candidate sources: stellar magnetic fields, magnetic flux from large radii around the black hole (the Lasso mechanism), and magnetic flux stored in the inner portion of a pre-existing accretion disk. We find that: observed stellar magnetic fields are insufficient to power these jets; the Lasso mechanism requires shallow radial magnetic field profiles and a mechanism to trap the magnetic flux brought by the debris in the vicinity of the black hole; pre-existing magnetic flux near the black hole in an accretion disk is the most plausible source.
Comments19 pages, 2 figures, 2 tables
