发表机构
Astronomisches Rechen-Institut, Zentrum für Astronomie der Universität Heidelberg; Department of Physics, New York University Abu Dhabi; Center for Astrophysics and Space Science (CASS), New York University Abu Dhabi; Dipartimento di Fisica, Sapienza, Universitá di Roma; Fesenkov Astrophysical Institute; National Astronomical Observatories, Chinese Academy of Sciences; Southwestern Institute for Astronomy Research, Yunnan University; Max Planck Computing and Data Facility; Kavli Institute for Astronomy and Astrophysics, Peking University（海德堡大学天文学计算研究所; 阿布扎比纽约大学物理系; 阿布扎比纽约大学天体物理学与空间科学中心; 罗马智慧大学物理系; 费森可夫天体物理研究所; 中国科学院国家天文台; 云南大学西南天文研究所; 马克斯·普朗克计算与数据设施; 北京大学柯维利天文学与天体物理研究所）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
本研究通过直接N体模拟核星团中的潮汐瓦解事件，提出新的部分质量吸积模型，发现主序恒星TDEs贡献约一半质量，吸积率早期峰值后快速下降。
AI 中文摘要
背景。核星团（NSCs）和超大质量黑洞（SMBHs）常常共存于星系中心，它们之间复杂的动力学相互作用影响着超大质量黑洞的增长。过于接近超大质量黑洞的恒星会被潮汐瓦解，其碎片的一部分被黑洞吸积。这类事件可能有助于贫气体星系中超大质量黑洞的增长。目的。我们的工作旨在通过数值模拟改进理解潮汐瓦解事件（TDEs）后恒星碎片质量吸积的理论框架。我们在一个完全自洽的动力学模型中嵌入中心超大质量黑洞的核星团进行直接N体模拟，以在一组试点模拟中测试新的潮汐瓦解事件吸积方案。方法。先前的潮汐瓦解事件方案使用固定的吸积半径，并假设恒星在瓦解后整个恒星质量都被吸积。在新的部分质量吸积模型中，添加到超大质量黑洞上的质量取决于被瓦解恒星的轨道偏心率和穿透因子。结果。我们发现，大多数涉及主序恒星的潮汐瓦解事件是边缘偏心或边缘双曲的，并且贡献约一半的恒星质量用于超大质量黑洞的增长，这与最近的流体动力学模拟一致。在所有模拟模型中，潮汐瓦解事件驱动的质量吸积率表现出早期峰值随后快速下降。初始超大质量黑洞质量较高的模型表现出更快的吸积率下降，这与更快速的损失锥耗竭和低效的补充一致。
英文摘要
Context. Nuclear star clusters (NSCs) and supermassive black holes (SMBHs) often coexist at the centers of galaxies, engaging in complex dynamical interactions that influence SMBH growth. Stars that approach the SMBH too closely are tidally disrupted, and a fraction of their debris is accreted onto the black hole. Such events may contribute to SMBH growth in gas-deficient galaxies. Aims. Our work aims to improve the theoretical framework for understanding the mass accretion of stellar debris following tidal disruption events (TDEs) through numerical simulations. We perform direct N-body simulations of an NSC with a central SMBH embedded in a fully self-consistent dynamical model to test a new TDE accretion prescription in a set of pilot simulations. Methods. The previous TDE prescription used a fixed accretion radius and assumed that the entire stellar mass was accreted after disruption. In the new partial-mass accretion model, the mass added to the SMBH depends on the orbital eccentricity and penetration factor of the disrupted star. Results. We find that most TDEs involving main-sequence stars are marginally eccentric or marginally hyperbolic and contribute approximately half of the stellar mass to SMBH growth, consistent with recent hydrodynamical simulations. In all simulated models, the TDE-driven mass accretion rate exhibits an early peak followed by a rapid decline. Models with higher initial SMBH masses exhibit a faster decline in the accretion rate, consistent with more rapid loss-cone depletion and inefficient replenishment
Comments14 pages, 14 figures, 2 tables. Submitted to Astronomy & Astrophysics
