Born in starbursts: exploring star formation in extreme environments

一场关于恒星形成的激烈争论：恒星的质量是由它们形成的云的湍流碎片决定的，还是由引力和辐射反馈过程之间的斗争决定的？两者似乎都是可能的，并且可能在不同的恒星形成环境中占主导地位，但人们对它们如何以及何时占主导地位知之甚少。这是天文学中一个长期存在的问题，因为恒星质量分布的形状——初始质量函数，或“IMF”——几乎是现代天体物理学所有领域的中心，包括观测宇宙学和行星形成。在这个博士学位课程中，学生将使用高分辨率的计算机模拟来研究恒星是如何在非常不同的环境中诞生的，比如那些在银河系中心发现的环境（剧烈）和那些在银河系外围发现的环境（平静）。通过探索不同的物理过程，如云湍流、磁场、气体的化学富集和恒星的辐射加热，他们将确定恒星的质量分布是如何被星际介质（ISM）的物理特性所塑造的。该学生将使用最先进的天体物理学流体代码Arepo，他们将在专门的超级计算中心（包括卡迪夫和国家设施）运行该代码。这个项目将向学生介绍各种各样的市场技能，包括高性能计算、代码开发和流体动力学。建议有扎实的编程背景（任何语言）。

A debate is raging in star formation: are the masses of stars set by the turbulent fragmentation of the clouds in which they form, or are they set by the fight between gravity and radiative feedback processes? Both appear to be possible, and perhaps dominate in different star-forming environments, but how and when they dominate is poorly understood. This is a long standing problem in astronomy, as the shape of the mass distribution of stars - the initial mass function, or "IMF" - is central nearly all fields or modern astrophysics, including observational cosmology and planet formation. In this PhD, the student will use high-resolution computer simulations to investigate how stars are born in very different environments, such as those found that are found at the centre of the Milky Way (violent) and those found in the outskirts of the Galaxy (quiescent). By exploring different physical processes, such as cloud turbulence, magnetic fields, chemical enrichment of the gas and radiative heating from stars, they will determine how the mass distribution of stars is shaped by the physics of the interstellar medium (ISM). The student will be using a state-of-the art astrophysics fluid code, Arepo, which they will run at dedicated supercomputing centres (including those at Cardiff and national facilities). This project will introduce the student to a wide variety of marketable skills, including high-performance computing, code development, and fluid dynamics. A solid background in coding is recommended (in any language).