Collaborative Research: The Radiation Magnetohydrodynamics of Tidal Disruption Events

潮汐破裂事件（TDE）是一种天体物理现象，当一颗星星足够接近超大质量黑洞（SMBH）时，会被黑洞的潮汐力拉开。 当这种情况发生时，星星的一部分质量被黑洞（BH）周围的吸积盘捕获，当这种物质福尔斯落入黑洞时，它会加速，产生电磁辐射，可以被天文望远镜探测到。 为了更好地研究这些事件，这可以帮助科学家了解强引力场，星系核心周围的空间以及吸积物理学，威斯康星大学密尔沃基分校和弗吉尼亚大学之间的研究合作将使用数值模拟来探测TDE的辐射磁流体动力学（对高度磁化等离子体发射的研究）以及物理学如何通过观测特征表现出来。 调查人员还将为学生和社区提供外展和教育机会，包括在密尔沃基的曼弗雷德奥尔森天文馆进行演讲，在计算科学暑期学校授课，并指导VA-NC联盟和UVA-Spelman交流暑期项目的本科生，目标是增加STEM研究领域中代表性不足的群体的参与。研究人员将使用数字代码MANGA和Athena++，他们已经为此进行了大量的算法投资，并且这些算法非常适合于这种TDEs的数值模拟。研究人员将逼真地模拟恒星从初始分裂到回落和随后的吸积的潮汐分裂。特别是，他们将确定磁场和辐射压力如何影响来自星星破坏的潮汐流，驱动流-流碰撞的演变，并影响随后的黑洞吸积，使他们能够探索TDE事件中超级爱丁顿吸积的物理学及其观测特征。 这项工作是至关重要的解释大量的事件，将被发现与目前的瞬态调查和维拉鲁宾天文台在不久的将来。这一奖项反映了NSF的法定使命，并已被认为是值得的支持，通过评估使用基金会的知识价值和更广泛的影响审查标准。

A tidal disruption event (TDE) is an astrophysical phenomenon that occurs when a star approaches sufficiently close to a supermassive black hole (SMBH) to be pulled apart by the black hole’s tidal force. As this happens, part of the star’s mass is captured in an accretion disk around the black hole (BH), and as this matter falls into the black hole, it accelerates, generating electromagnetic radiation, which can be detected by astronomical telescopes. To better study these events, which can help scientists understand strong gravitational fields, the space around the cores of galaxies, and physics of accretion, a research collaboration between the University of Wisconsin-Milwaukee and the University of Virginia will use numerical simulations to probe the radiation magnetohydrodynamics (the study of emission from highly magnetized plasmas) of TDEs and how the physics is manifest through observational signatures. The investigators will also provide outreach and educational opportunities for students and the community, including presentations at the Manfred Olson Planetarium in Milwaukee, teaching at a summer school in computational science, and mentoring undergraduate students in the VA-NC Alliance and UVA-Spelman exchange summer programs, with the goal of increasing participation of underrepresented groups in STEM research fields.The investigators will use the numerical codes MANGA and Athena++, for which they have made significant algorithmic investments, and which are ideal for numerical simulations of this TDEs. The investigators will realistically model the tidal disruption of stars from initial disruption to fallback and subsequent accretion. In particular, they will determine how magnetic fields and radiation pressure affect the tidal streams from the star’s disruption, drive the evolution of stream-stream collisions, and impact the subsequent accretion onto the black hole, allowing them explore the physics of super-Eddington accretion in TDE events and their observational signatures. This work is crucial for the intepretation of the the large number of events that will be discovered with the current transient surveys and the Vera Rubin Observatory in the near future.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.