WoU-MMA: Role of the Dynamo Effect in Neutron Star Mergers

WoU-MMA：发电机效应在中子星合并中的作用

• 批准号: 2206756
• 负责人: Amitava Bhattacharjee
• 金额: $ 60万
• 依托单位: Princeton University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-07-01 至 2025-06-30
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2206756&HistoricalAwards=false
• 关键词: WoU; MMA; Role; Dynamo; Effect

When neutron stars, which are some of the most spectacular compact objects in the Universe, merge, they launch powerful jets that move nearly at the speed of light. To predict the formation of these jets, it is necessary to understand how accompanying magnetic fields are spontaneously produced during neutron star mergers. The present award will focus on the so-called “dynamo effect,” which accounts for the emergence of magnetic fields from turbulence. Understanding the role of the dynamo effect is crucial for our understanding of multi-messenger astrophysical sources and thus addresses goals of NSF's "Windows on the Universe: The Era of Multi-Messenger Astrophysics".The magnetic field necessary for launching astrophysical jets may be generated in at least two locations: in the shear layer between the neutron stars when they first come into contact, and, if the remnant is a black hole, in the flow of accreting material immediately following the merger. The goal of this effort is to elucidate from first principles the dynamo produced by the Kelvin-Helmholtz instabilities in the pre-merger phase, and the magnetorotational instability and the Rayleigh-Taylor instability in the post-merger phase. The award will also support engagement with the Princeton Pre-Doctoral Fellowship Initiative, strengthen the current partnership of Princeton University with the American Physical Society Bridge Program, and enable involvement of undergraduates in synergistic research projects.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.

中子星是宇宙中最壮观的紧凑物体之一，当它们合并时，它们会发射出几乎以光速移动的强大射流。 为了预测这些喷流的形成，有必要了解伴随的磁场是如何在中子星星合并过程中自发产生的。目前的奖项将集中在所谓的“发电机效应”，这是磁场从湍流中出现的原因。理解发电机效应的作用对于我们理解多信使天体物理学源至关重要，因此也解决了美国国家科学基金会“宇宙之窗：多信使天体物理学时代”的目标。发射天体物理学喷流所需的磁场可能至少在两个位置产生：在中子星第一次接触时的剪切层中，如果残余物是黑洞，在合并后立即产生的吸积物质流中。这项工作的目标是阐明从第一原理的发电机产生的Kelvin-Helmholtz不稳定性在合并前阶段，磁旋转不稳定性和瑞利-泰勒不稳定性在合并后阶段。该奖项还将支持与普林斯顿大学博士前奖学金计划的合作，加强普林斯顿大学与美国物理学会桥梁计划的现有合作关系，并使本科生能够参与协同研究项目。该奖项反映了NSF的法定使命，并通过使用基金会的智力价值和更广泛的影响审查标准进行评估，被认为值得支持。

项目成果

On large-scale dynamos with stable stratification and the application to stellar radiative zones

• DOI: 10.1093/mnras/stac2676
• 发表时间: 2022-03
• 作者: V. Skoutnev;J. Squire;Ashis Bhattacharjee