Collaborative Research: WoU-MMA Constraining the nuclear equation of state and population of neutron star mergers through observations of transient and persistent phenomena

合作研究：WoU-MMA 通过观察瞬态和持续现象来约束中子星并合的核状态方程和布居数

• 批准号: 2206322
• 负责人: Andrew Steiner
• 金额: $ 23.66万
• 依托单位: University of Tennessee Knoxville
• 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: 2022-12-01 至 2025-11-30
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2206322&HistoricalAwards=false
• 关键词: Collaborative; Research; WoU; MMA; Constraining

Neutron stars (NSs) are formed when a massive star reaches the end of its life: the outer layers of the star are ejected in a violent explosion but the core of the star collapses to form a small, dense remnant. NSs that form a binary system with another NS sometimes in-spiral and merge, producing gravitational waves and a bright transient that is thousands of times more luminous than a nova (a so-called kilonova). NS-NS mergers have been detected by the NSF-funded Laser Interferometer Gravitational wave Observatory (LIGO). A team from the Rochester Institute of Technology and the University of Tennessee Knoxville will continue their program to use advanced computational models to better understand NS-NS mergers and NS physics. They will produce realistic models of the kilonova explosion, improve estimates of the neutron mass distribution, and better understand neutron star populations. The models will be benchmarked against gravitational wave and electromagnetic detections of NS-NS mergers. The program includes training and mentoring of graduate students and postdoctoral researchers; participation in a Rochester Institute of Technology program (ROAR) that introduces high school students from underrepresented minorities to research; and development of a new undergraduate course at the University of Tennessee Knoxville focused on gravitational waves. The detailed science goals of the proposal are; extend ongoing work to produce more systematic kilonova models, calibrated to simulations and exploring relevant systematic uncertainties; incorporate rapid r-process observations systematically into joint inference about NS population properties and the equation of state (EOS), allowing for alternatives, to assess the origin of r-process elements; use the tools developed as part of this program to reconstruct the population of NS, the nuclear EOS, and the origin of r-process elements; and assess the ability of the tools to draw these inferences. The proposed research involves producing realistic models of the kilonova explosion that occurs when neutron stars collide and merge. These models will be benchmarked against gravitational wave and electromagnetic detections of NS-NS mergers, thereby improving estimates of the neutron mass distribution and better understanding neutron star populations. Thus, this project is aligned with the science mission of the Windows on the Universe: Multi-Messenger Astronomy (WoU-MMA) Big Idea.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（NS）是在一颗大质量恒星到达其生命终点时形成的：恒星的外层在剧烈的爆炸中被弹出，但恒星的核心塌陷形成一个小而致密的残余物。与另一个 NS 形成双星系统的 NS 有时会螺旋并合并，产生引力波和明亮的瞬变，其亮度比新星（所谓的千新星）亮数千倍。 NS-NS 合并已被 NSF 资助的激光干涉仪引力波天文台 (LIGO) 探测到。来自罗彻斯特理工学院和田纳西州诺克斯维尔大学的一个团队将继续他们的计划，使用先进的计算模型来更好地理解 NS-NS 合并和 NS 物理学。他们将制作千新星爆炸的真实模型，改进对中子质量分布的估计，并更好地了解中子星数量。这些模型将以 NS-NS 合并的引力波和电磁探测为基准。该计划包括对研究生和博士后研究人员的培训和指导；参与罗彻斯特理工学院项目 (ROAR)，该项目向来自代表性不足的少数族裔的高中生介绍研究；田纳西大学诺克斯维尔分校开发了一门新的本科课程，重点关注引力波。该提案的详细科学目标是：扩展正在进行的工作以产生更系统的千新星模型，根据模拟进行校准并探索相关的系统不确定性；将快速 r 过程观测系统地纳入有关 NS 总体属性和状态方程 (EOS) 的联合推断中，允许替代方案，以评估 r 过程元素的起源；使用作为该计划一部分开发的工具来重建 NS 群体、核 EOS 和 r 过程元素的起源；并评估工具得出这些推论的能力。拟议的研究涉及制作中子星碰撞和合并时发生的千新星爆炸的真实模型。这些模型将以 NS-NS 合并的引力波和电磁探测为基准，从而改进对中子质量分布的估计并更好地了解中子星数量。因此，该项目与宇宙之窗的科学使命：多信使天文学 (WoU-MMA) 大创意相一致。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

Deducing neutron star equation of state from telescope spectra with machine-learning-derived likelihoods

利用机器学习推导的似然度从望远镜光谱中推导出中子星状态方程

• DOI: 10.1088/1475-7516/2023/12/022
• 发表时间: 2023
• 期刊: Journal of Cosmology and Astroparticle Physics
• 影响因子: 6.4
• 作者: Farrell, Delaney;Baldi, Pierre;Ott, Jordan;Ghosh, Aishik;Steiner, Andrew W.;Kavitkar, Atharva;Lindblom, Lee;Whiteson, Daniel;Weber, Fridolin
• 通讯作者: Weber, Fridolin