Towards a Complete Understanding of Stellar Feedback in Massive Star Formation

安娜·罗森被授予美国国家科学基金会天文学和天体物理学奖学金，以在加州大学圣地亚哥分校开展一项研究和教育计划。罗森将对来自辐射、恒星风、星流和宇宙射线的恒星反馈--注入星际介质的能量和动量--如何影响大质量恒星和星团的形成进行数值模拟。这项研究的结果将使天文学家更好地了解反馈在恒星形成和星系形成过程中的作用。除了这项研究，罗森将开展以非传统和代表性不足的社区大学生为中心的教育和推广活动，为大学的新生提供研究指导和专业发展，并制作向社区大学生介绍计算天体物理学和科学计算的视频。罗森将通过执行一套跟踪大质量星团内单个大质量恒星形成的辐射-磁流体力学模拟，探索各种反馈机制如何在个人和星团尺度上限制大质量恒星的形成。利用这些模拟，她将确定大质量恒星形成所需的初始条件以及由此产生的HII区域的性质。此外，通过将现实的尘埃物理和各向异性宇宙线扩散纳入新的建模框架，她将评估恒星反馈如何限制恒星质量，控制分子云中的恒星形成速度，并潜在地在大范围内喷射气体。她的结果将带来更好的反馈模型，这些模型将用于未来的宇宙学模拟，并有助于多波长观测。这一奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

Anna Rosen is awarded an NSF Astronomy and Astrophysics Fellowship to carry out a program of research and education at the University of California, San Diego. Rosen will perform numerical simulations of how stellar feedback – the energy and momentum injected into the interstellar medium – from radiation, stellar winds, outflows, and cosmic rays affects the formation of massive stars and star clusters. Results from the study will allow astronomers to better understand the role of feedback in the processes of star formation and galaxy formation. Alongside this research, Rosen will conduct education and outreach activities centered around non-traditional and underrepresented community college students, providing research mentoring and professional development for incoming students at the University, and developing videos introducing computational astrophysics and scientific computing to community college students.Rosen will explore how various feedback mechanisms limit massive star formation on both the individual and cluster scales by performing a suite of radiation-magnetohydrodynamic simulations that follow the formation of individual massive stars within massive star clusters. Using these simulations, she will determine the initial conditions required for massive star formation and the properties of the resulting HII regions. Additionally, by including realistic dust physics and anisotropic cosmic ray diffusion into a new modeling framework, she will assess how stellar feedback limits stellar masses, controls star formation rates in molecular clouds, and potentially ejects gas over large scales. Her results will lead to better feedback models that will be used in future cosmological simulations and aid multi-wavelength observations.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.