Star Formation, ISM, and Winds in Bursty vs. Steady Galaxies

恒星形成、ISM 和爆发性星系与稳定星系中的风

• 批准号: 2307327
• 负责人: Claude-Andre Faucher-Giguere
• 金额: $ 54.08万
• 依托单位: Northwestern University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-09-01 至 2026-08-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2307327&HistoricalAwards=false
• 关键词: Star; Formation; ISM; Winds; Bursty

Stars form in galaxies wherever molecular gas becomes sufficiently cold and dense to become gravitationally unstable, which initiates fragmentation and subsequent collapse. Once formed, however, stars can profoundly affect their surroundings through the energy injected by supernovae, ultraviolet radiation, and fast stellar winds, processes collectively referred to as "stellar feedback." Stellar feedback can suppress the star formation rate (SFR), regulate the overall mass growth of a galaxy, and shape its multi-phase interstellar medium (ISM). While there has been much progress in modeling stellar feedback, previous work has focused primarily on Milky Way-like systems, where the SFR is fairly constant. However, star formation in low-mass and/or high-redshift galaxies tend to have highly episodic or "bursty" SFRs, where stellar feedback may work in fundamentally different ways relative to local spirals. The principal investigator and team will extend stellar feedback theory from "steady" systems to bursty ones, and in particular, the small and highly gas rich examples recently found at high-redshift that are likely the progenitors of Milky Way-like systems, and which are the focus of many observational studies by state-of-the-art ground- based and space-based observatories. In addition to a postdoc, this award will support the mentoring of three undergraduate researchers, outreach events at Chicago's Adler Planetarium and other public events, and improvements in FIREFLY, an interactive scientific visualization tool.The proposed research will be centered on a large suite of zoom-in simulations that resolve the ISM of individual galaxies in a cosmological context, and which self-consistently model the transition from bursty to steady galaxies. The simulations include all the main forms of stellar found in galaxies from dwarfs to super-L*. The project will focus on three core science issues: (1) the applicability of “equilibrium disk” or “pressure balance” models for the origin of the Kennicutt-Schmidt star formation law, (2) the dynamical and thermodynamic properties of the ISM and its relationship to the circumgalactic medium, and (3) the launching of galactic winds and galactic fountains in bursty vs. steady galaxies. Variants of the simulations will include additional physical processes (e.g., magnetic fields, cosmic rays, and non-equilibrium ISM chemistry) to test how the results depend on these additional variables. Observational predictions will be made to test the simulation predictions in the different regimes.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.

恒星在星系中形成，只要分子气体变得足够冷和稠密，从而导致引力不稳定，就会引发碎裂和随后的坍缩，然而，恒星一旦形成，就会通过超新星、紫外线辐射和快速恒星风注入的能量，深刻地影响它们的周围环境。这些过程统称为“恒星反馈”。恒星反馈可以抑制恒星形成速率（SFR），调节星系的整体质量增长，并塑造其多相星际介质（ISM）。在恒星反馈建模方面已经取得了很大进展，之前的工作主要集中在类银河系系统上，其中恒星形成率相当恒定，然而，低质量和/或高红移星系中的恒星形成往往具有高度偶发性或高度偶发性。 “突发”恒星形成率，其中恒星反馈可能以与局部螺旋截然不同的方式发挥作用，首席研究员和团队将把恒星​​反馈理论从“稳定”系统扩展到突发系统，特别是最近的小型且​​高度富含气体的例子。发现于高红移可能是类银河系系统的前身，也是最先进的地面和太空天文台许多观测研究的焦点。除了博士后之外，该奖项还将支持对三名本科生研究人员的指导、芝加哥阿德勒天文馆的外展活动和其他公共活动，以及交互式科学可视化工具 FIREFLY。拟议的研究将集中于一整套放大模拟，以解决改进问题宇宙学背景下单个星系的 ISM，并且自洽地模拟了从爆发星系到稳定星系的转变。该模拟包括从矮星系到超 L* 星系中发现的所有主要恒星形式。科学问题：（1）“平衡盘”或“压力平衡”模型对于肯尼卡特-施密特恒星形成定律起源的适用性，（2）动力学和ISM 的热力学特性及其与环星系介质的关系，以及（3）在爆发星系和稳定星系中发射星系风和星系喷泉。模拟的变体将包括额外的物理过程（例如磁场、宇宙射线、和非平衡 ISM 化学），以测试结果如何取决于这些附加变量，以测试不同状态下的模拟预测。该奖项。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，NSF 的法定使命被认为值得支持。

项目成果

Born this way: thin disc, thick disc, and isotropic spheroid formation in FIRE-2 Milky Way–mass galaxy simulations

• DOI: 10.1093/mnras/stad1806
• 发表时间: 2022-10
• 期刊: Monthly Notices of the Royal Astronomical Society
• 影响因子: 4.8
• 作者: Sijie Yu;J. Bullock;Alex Gurvich;Zachary Hafen;J. Stern;M. Boylan-Kolchin;C. Faucher-Giguère

Probing bursty star formation by cross-correlating extragalactic background light and galaxy surveys

通过河外背景光和星系调查的互相关来探测突发恒星的形成

• DOI: 10.1093/mnras/stad2000
• 发表时间: 2023
• 期刊: Monthly Notices of the Royal Astronomical Society
• 影响因子: 4.8
• 作者: Sun, Guochao;Lidz, Adam;Faisst, Andreas L.;Faucher-Giguère, Claude-André
• 通讯作者: Faucher-Giguère, Claude-André

A Unified Model for the Coevolution of Galaxies and Their Circumgalactic Medium: The Relative Roles of Turbulence and Atomic Cooling Physics

星系及其环星系介质共同演化的统一模型：湍流和原子冷却物理的相对作用

• DOI: 10.3847/1538-4357/acf3ea
• 发表时间: 2023
• 期刊: The Astrophysical Journal
• 作者: Pandya, Viraj;Fielding, Drummond B.;Bryan, Greg L.;Carr, Christopher;Somerville, Rachel S.;Stern, Jonathan;Faucher-Giguère, Claude-André;Hafen, Zachary;Anglés-Alcázar, Daniel;Forbes, John C.
• 通讯作者: Forbes, John C.

Seen and unseen: bursty star formation and its implications for observations of high-redshift galaxies with JWST

可见与不可见：爆发式恒星形成及其对 JWST 观测高红移星系的影响

• DOI: 10.1093/mnras/stad2902
• 发表时间: 2023
• 期刊: Monthly Notices of the Royal Astronomical Society
• 影响因子: 4.8
• 作者: Sun, Guochao;Faucher-Giguère, Claude-André;Hayward, Christopher C.;Shen, Xuejian
• 通讯作者: Shen, Xuejian

What causes the formation of discs and end of bursty star formation?

是什么导致了圆盘的形成和爆发式恒星形成的结束？

• DOI: 10.1093/mnras/stad1902
• 发表时间: 2023
• 期刊: Monthly Notices of the Royal Astronomical Society
• 影响因子: 4.8
• 作者: Hopkins, Philip F.;Gurvich, Alexander B.;Shen, Xuejian;Hafen, Zachary;Grudić, Michael Y.;Kurinchi-Vendhan, Shalini;Hayward, Christopher C.;Jiang, Fangzhou;Orr, Matthew E.;Wetzel, Andrew
• 通讯作者: Wetzel, Andrew