Collaborative Research: Petascale Simulations of Binary Neutron Star Mergers

合作研究：双中子星合并的千万亿次模拟

• 批准号: 1811352
• 负责人: Philipp Moesta
• 金额: $ 0.55万
• 依托单位: University of California-Berkeley
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2018
• 资助国家: 美国
• 起止时间: 2018-04-01 至 2019-09-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1811352&HistoricalAwards=false
• 关键词: Collaborative; Research; Petascale; Simulations; Binary

The era of multimessenger astronomy has been inaugurated with the extraordinary detection of the collision of two neutron stars (NSs) by the Laser Interferometer Gravitational-Wave Observatory (LIGO), and the subsequent observations by X-ray, optical, infrared, and radio facilities. These observations have started to revolutionize our understanding of many areas in physics, including the origins of the heavy elements, like silver, gold, and platinum. However, they also pose many pressing open questions. This project will make use of the Blue Waters supercomputer to address these open questions. State-of-the-art NS merger simulations will be performed on the Blue Waters supercomputer to examine all the different possible NS collision scenarios to understand the fundamental physical processes that generated the observation data. This will be followed by extremely high-resolution simulations considering the post-merger evolution. Simulation results will be made publicly available, and dissemination via movies, public lectures and school visits are planned.A systematic study of the evolution of NS binary systems compatible with the observed NS collision, GW170817, will be performed by means of merger simulations on Blue Waters, employing sophisticated microphysics and neutrino treatment. These simulations will ascertain the viability of tidal torques and shocks as mechanisms for the ejection of matter during mergers, which in turn powers the observed optical and infrared transients and synthesizes heavy elements. The impact of the NS equation of state (EOS) will be evaluated by considering a set of 3 EOSs spanning the range of the current nuclear uncertainties. The range of possible outcomes of the merger as a function of the binary parameters and EOSs will be assessed. High-resolution general-relativistic magnetohydrodynamics simulations of the merger remnant will be performed, with sufficient resolution to determine the magnetorotational instability (MRI) and the angular-momentum redistribution in the remnant while employing a microphysical treatment of the NS matter. These simulation results will ascertain the role of magnetohydrodynamics processes in determining the lifetime of the remnant and the observational signatures of an early or delayed black-hole formation. The role played by magnetized winds in the powering of the optical and infrared emissions and their nucleosynthetic yields will be assessed. In addition, this project will develop significant improvements to current open-source codes, and all improvements will be released to the community.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.

激光干涉引力波天文台 (LIGO) 对两颗中子星 (NS) 碰撞的非凡探测，以及 X 射线、光学、红外和无线电设施的后续观测，开启了多信使天文学时代。这些观察结果已经开始彻底改变我们对物理学许多领域的理解，包括银、金和铂等重元素的起源。然而，他们也提出了许多紧迫的悬而未决的问题。 该项目将利用 Blue Waters 超级计算机来解决这些悬而未决的问题。 最先进的 NS 合并模拟将在 Blue Waters 超级计算机上进行，以检查所有不同可能的 NS 碰撞场景，以了解生成观测数据的基本物理过程。随后将进行考虑合并后演变的极高分辨率模拟。 模拟结果将公开，并计划通过电影、公开讲座和学校参观等方式进行传播。将通过 Blue 上的合并模拟对与观测到的 NS 碰撞 GW170817 兼容的 NS 双星系统的演化进行系统研究沃特世采用复杂的微物理和中微子处理。 这些模拟将确定潮汐扭矩和冲击作为合并过程中物质喷射机制的可行性，这反过来又为观测到的光学和红外瞬变提供动力并合成重元素。 NS 状态方程 (EOS) 的影响将通过考虑涵盖当前核不确定性范围的一组 3 个 EOS 来评估。将评估作为二元参数和 EOS 函数的合并可能结果的范围。将对合并残余物进行高分辨率广义相对论磁流体动力学模拟，具有足够的分辨率来确定磁旋转不稳定性（MRI）和残余物中的角动量重新分布，同时对 NS 物质进行微观物理处理。这些模拟结果将确定磁流体动力学过程在确定残余物的寿命以及早期或延迟黑洞形成的观测特征中的作用。将评估磁化风在为光学和红外发射提供动力及其核合成产量中所发挥的作用。 此外，该项目将对当前开源代码进行重大改进，所有改进都将发布给社区。该奖项反映了 NSF 的法定使命，并通过使用基金会的智力优点和更广泛的影响审查进行评估，认为值得支持标准。