Theoretical Studies in Interstellar Astrophysics

在中小尺度尺度上，星际介质的动力学是由恒星的能量注入所控制的，特别是电离辐射、风和大质量恒星的超新星爆炸。麦基博士将研究在不均匀介质中，在孤立的大质量恒星和这样的恒星群周围电离氢区域的演化。将计算在电离氢区域爆炸的超新星残余物的动力学和光谱，并评估其对残余物观测统计的影响。来自一群大质量恒星的超新星在星际介质中产生了一个“超级气泡”；这些结构的动力学将被研究，应用于银河系和星爆星系。一个功能强大的新型流体力学计算机代码将用于解决由能量注入引起的星际气体动力学中的一些基本问题，包括爆炸波与星际云的相互作用。星际激波的光谱为天文学家研究恒星能量注入效应提供了必要的诊断工具，并计划对分子气体中的激波结构进行全面的研究。大量的计算将提出这样的假设，即星际水脉泽是由密集分子气体中的激波引起的。恒星在其生命期间通过辐射和恒星风为星际介质提供能量，对一些恒星来说，在它们死亡时通过超新星爆炸为其提供能量。这种能量最终被辐射到星系间空间，所以星际介质的能量可以被看作是一种能量流，它以几种形式起源于恒星，通过星际介质向外流动，最终以辐射、宇宙射线的形式离开银河系，在极端情况下，风。星际天体物理学的核心问题之一是了解恒星能量注入如何在我们的银河系和其他星系中产生星际介质的物理条件和形态。麦基博士的研究将集中在大质量恒星的能量注入上，这在注入星际介质的能量中占主导地位。

The dynamics of the interstellar medium on small and intermediate scale sizes is governed by energy injection from stars, particularly the ionizing radiation, winds, and supernova explosions of massive stars. The evolution of ionized hydrogen regions, both around isolated massive stars and clusters of such stars, in an inhomogeneous medium will examined by Dr. McKee. The dynamics and spectra of the remnants of supernovae which explode in ionized hydrogen regions will be calculated, and the implications for the observed statistics of remnants assessed. Supernovae from a cluster of massive stars create a "superbubble" in the interstellar medium; the dynamics of such structures will be investigated, with applications both to the Galaxy and to starburst galaxies. A powerful new hydrodynamics computer code will be used to address some fundamental problems in interstellar gas dynamics posed by energy injection, including the interaction of a blast wave with an interstellar cloud. The spectra of interstellar shocks provide astronomers with essential diagnostic tools for the study of the effects of stellar energy injection, and a comprehensive attack on the structure of shocks in molecular gas is planned. Extensive calculations will develop the hypothesis that interstellar water masers are due to shocks in dense molecular gas. Stars energize the interstellar medium through radiation and stellar wiinds during the star's life, and for some stars, through supernova explosions at their death. This energy is eventually radiated into intergalactic space, so the energization of the interstellar medium may be viewed as an energy flow which originates in stars in several forms, streams outward through the interstellar medium, and finally leaves the Galaxy in the form of radiation, cosmic rays, and in extreme cases, a wind. One of the central problems in interstellar astrophysics is to understand how stellar energy injection produces the physical conditions and morphology of the interstellar medium, both in our Galaxy and in other galaxies. Dr. McKee's research will focus on energy injection by massive stars, which dominates the energy injection into the interstellar medium.