Multidimensional Radiation-Hydrodynamic Simulations of Core-Collapse Supernovae, Winds from Oblate Hot Stars, and Explosions of Rapidly-Rotating Stars

Jeremiah Murphy博士被授予美国国家科学基金会天文学和天体物理学博士后奖学金，在华盛顿大学开展研究和教育项目。墨菲博士将完成BETHE的开发，这是一个多角度，多能组，多维，随时间变化的辐射流体动力学代码。辐射流体动力学是天体物理学的一个核心学科，对于许多现象来说，非球面现象要么伴随着基本理论，要么是基本理论。BETHE采用新颖的混合帧辐射传输，实现简单，可推广到多个维度，准确且相对快速。流体动力学求解器是一种任意拉格朗日-欧拉（ALE）方法，并使用任意网格，提供了定制网格以适应计算挑战的灵活性。总之，这些特征允许对天体物理现象进行独特的多维模拟。特别是，Murphy博士将(1)解决核心坍缩超新星的中微子和声学机制的可行性，(2)模拟来自扁型热恒星的风，以及(3)研究在快速旋转恒星的背景下，提出的发光-蓝色变量爆发机制是否可以再现船底座埃塔的观测结果。墨菲还将积极参与天文学预专业项目（Pre-MAP），该项目旨在保留华盛顿大学天文系的多元化学生群体。Pre-MAP针对来自传统上代表性不足的科学群体（女性、第一代和低收入大学生、非洲裔美国人、拉丁裔美国人、美洲原住民、东南亚人和太平洋岛民）的一年级学生，其主要目标有两个：通过研究激发学生的兴趣和热情，并提供一个支持性社区，使他们能够成功。墨菲博士的角色将是指导Pre-MAP学生，提供模拟结果分析，支持实地考察和研究，最重要的是，评估和改进程序。

Dr. Jeremiah Murphy is awarded an NSF Astronomy and Astrophysics Postdoctoral Fellowship to carry out a program of research and education at the University of Washington. Dr. Murphy will complete development of BETHE, a multi-angle, multi-energy-group, multidimensional, time-dependent radiation-hydrodynamics code. Radiation hydrodynamics is a core subject in astrophysics, and for many phenomena asphericities either accompany or are fundamental to the underlying theory. BETHE uses novel mixed-frame radiation transport that is straightforward to implement, generalizable to multiple dimensions, accurate and relatively fast. The hydrodynamics solver is an Arbitrary Lagrangian-Eulerian (ALE) method and uses arbitrary grids providing flexibility to tailor the grid to the computational challenge. Together, these characteristics allow for unique multidimensional simulations of astrophysical phenomena. In particular, Dr. Murphy will (1) address the viability of the neutrino and acoustic mechanisms for core-collapse supernovae, (2) simulate winds from oblate hot stars, and (3) investigate whether proposed mechanisms for luminous-blue-variable outbursts can reproduce, in the context of rapidly rotating stars, the observations of Eta Carinae's Homunculus.Dr. Murphy will also be actively involved with the Pre-Major in Astronomy Program (Pre-MAP), which seeks to retain a diverse student body in the University of Washington Astronomy Department. Pre-MAP targets first-year students from traditionally underrepresented groups in the sciences (women, first-generation and low-income college students, African Americans, Latinos, Native Americans, Southeast Asians and Pacific Islanders) with two primary goals: to engage students' interest and enthusiasm through research and to provide a supportive community, enabling their success. Dr. Murphy's roles will be to mentor Pre-MAP students, to offer simulation results to analyze, to support field trips and research, and, most importantly, to evaluate and improve the program.