Collaborative Research: Stars from Clouds - Turbulence, Magnetic Fields and Dynamics of Forming Star Clusters

合作研究：云中的恒星——湍流、磁场和形成星团的动力学

• 批准号: 2009674
• 负责人: Jonathan Tan
• 金额: $ 29.64万
• 依托单位: University of Virginia Main Campus
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-09-01 至 2024-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2009674&HistoricalAwards=false
• 关键词: Collaborative; Research; Stars; Clouds; Turbulence

Stars are formed in molecular clouds of gas in galaxies. Astronomers seek to understand what causes a particular region of a molecular cloud to form a star. This seemingly simple question is at the heart of several basic research frontiers of modern astrophysics, including galaxy formation and the origin of stellar clusters. The investigators plan numerical simulations of magnetized molecular clouds that include important physical processes and a variety of initial conditions. The investigators will compare their models to radio wavelength observations of Giant Molecular Clouds (GMCs) from NSF’s Atacama Large Millimeter/submillimeter Array (ALMA). In their studies of the structure and kinematics of GMCs, they will focus on long, filamentary clouds that have been found in the Galactic plane. The investigators will test models of dynamics of young stellar systems using data from ongoing optical surveys of thousands of young stars. The investigators will train undergraduate and graduate students in advanced research methods, which will be of general benefit in their future careers in either science or industry. The investigators plan a new “Stars from the Clouds” presentation for public outreach programs.The team plans numerical simulations of the dynamics of magnetized molecular clouds, including clouds extracted from larger scale shearing galactic disk simulations, giant molecular cloud collisions and idealized periodic box turbulence. A focus of the simulations is inclusion of non-ideal magneto-hydrodynamic processes of ambipolar and reconnection diffusion in adaptive mesh refinement simulations, which also model astrochemistry and predict metrics to be compared to observations. For the stellar cores, the priority will be study of spatial distributions and populations of pre-stellar and proto-stellar cores.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.

恒星形成于星系中的气体分子云中。 天文学家试图了解是什么导致分子云的特定区域形成星星。这个看似简单的问题是现代天体物理学的几个基础研究前沿的核心，包括星系形成和星团的起源。 研究人员计划对磁化分子云进行数值模拟，其中包括重要的物理过程和各种初始条件。研究人员将把他们的模型与美国国家科学基金会阿塔卡马大型毫米/亚毫米阵列（阿尔马）的巨型分子云（GMC）的无线电波长观测结果进行比较。 在他们对GMC的结构和运动学的研究中，他们将专注于在银河系平面上发现的长形云。 研究人员将使用正在进行的数千颗年轻恒星的光学调查数据来测试年轻恒星系统的动力学模型。研究人员将对本科生和研究生进行先进研究方法的培训，这将对他们未来的科学或工业职业生涯产生普遍影响。 研究人员计划为公共宣传项目做一个新的“来自云的星星”演示。该团队计划对磁化分子云的动力学进行数值模拟，包括从更大规模的剪切星系盘模拟中提取的云，巨大的分子云碰撞和理想化的周期性盒子湍流。模拟的一个重点是纳入非理想的磁流体动力学过程的双极和重连扩散的自适应网格细化模拟，这也模拟天体化学和预测指标进行比较的意见。对于恒星核心，优先考虑的是星前和原恒星核心的空间分布和种群研究。该奖项反映了NSF的法定使命，并通过使用基金会的知识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

What Sets the Star Formation Rate of Molecular Clouds? The Density Distribution as a Fingerprint of Compression and Expansion Rates

是什么决定了分子云的恒星形成率？

• DOI: 10.3847/1538-4357/ace897
• 发表时间: 2023
• 期刊: The Astrophysical Journal
• 作者: Appel, Sabrina M.;Burkhart, Blakesley;Semenov, Vadim A.;Federrath, Christoph;Rosen, Anna L.;Tan, Jonathan C.
• 通讯作者: Tan, Jonathan C.

A Census of Outflow to Magnetic Field Orientations in Nearby Molecular Clouds

附近分子云磁场方向流出量的普查

• DOI: 10.3847/1538-4357/aca153
• 发表时间: 2022
• 期刊: The Astrophysical Journal
• 作者: Xu, Duo;Offner, Stella S.;Gutermuth, Robert;Tan, Jonathan C.
• 通讯作者: Tan, Jonathan C.