致密天体并合与微潮汐瓦解事件：致密恒星环境的多信使探针
Compact Object Mergers and Micro-Tidal Disruption Events: A Multi-Messenger Probe of Dense Stellar Environments
- Stony Brook University（石溪大学）
- Johns Hopkins University（约翰斯·霍普金斯大学）
机构由 AI 辅助整理，请以论文原文为准。
中文总结 AI 辅助
本研究通过模拟致密星团，发现微潮汐瓦解事件数量超过并合数倍，并揭示其可产生高自旋黑洞及填充低质量间隙的动力学途径。
中文摘要 AI 辅助
球状星团和年轻大质量星团等致密恒星环境既会产生可在引力波中探测到的致密天体并合，也会产生可在电磁波段观测到的潮汐瓦解事件。我们利用Rapster代码进行快速蒙特卡洛星团模拟，研究了这些环境中的致密天体并合、潮汐瓦解事件和微潮汐瓦解事件（$μ$TDEs）。该模拟扩展了对中子星（NS）和黑洞（BH）在盘吸积下自旋演化的统一处理，涵盖从NS到BH的转变，以及由单个致密天体和BH-BH双星进行瓦解的新动力学通道。通过模拟跨越十种模型变体和两种形成历史的$10^5$个星团，我们发现BH-BH并合率密度在$z\approx2$-$3$处达到峰值，为几十${\rm Gpc}^{-3}\\,{\rm yr}^{-1}$，与当地LVK速率一致，而$μ$TDEs的累计数量超过并合数量的数倍。由于我们仅包含动力学形成的双星，约$90\\%$的$μ$TDEs通过单个致密天体-恒星遭遇发生，我们的速率是保守的下限。$μ$TDEs期间的顺行吸积会使致密天体自旋加速，为产生高自旋黑洞提供了一条纯动力学、随机取向的途径，并可驱动中子星吸积诱导坍缩为黑洞，从而填充低质量间隙。
英文摘要
Dense stellar environments such as globular clusters and young massive clusters produce both compact-object mergers detectable in gravitational waves and tidal disruption events observable electromagnetically. We investigate compact-object mergers, tidal disruption events, and micro-tidal disruption events ($μ$TDEs) in these environments using rapid Monte Carlo star-cluster simulations with the Rapster code, extended with a unified treatment of neutron-star (NS) and black-hole (BH) spin evolution under disk accretion across the NS-to-BH transition, as well as new dynamical channels for disruptions by single compact objects and by BH-BH binaries. Simulating $10^5$ clusters across ten model variations and two formation histories, we find a BH-BH merger-rate density peaking at $z\approx2$-$3$ at several tens ${\rm Gpc}^{-3}\,{\rm yr}^{-1}$, consistent with the local LVK rate, while the cumulative number of $μ$TDEs exceeds that of mergers by a factor of a few. Since we include only dynamically formed binaries, $\approx90\%$ of $μ$TDEs proceed through single compact-object-star encounters, and our rates are conservative lower limits. Prograde accretion during $μ$TDEs spins up compact objects, providing a purely dynamical, randomly oriented pathway for producing high-spin BHs, and can drive accretion-induced collapse of NSs to BHs that populate the lower mass gap.
