The effect of the environment on the Interstellar Medium of disk galaxies

星系内恒星之间的空间被星际介质(ISM)填满，它的演化是一个多相、可压缩、磁化和湍流的介质。它的复杂和非线性物理涉及到巨大的空间和时间尺度。计算能力的限制仍然迫使我们做出选择：要么研究亚PC分辨率的小ISM体积，要么研究一个分辨率约为50 PC的星系的全球ISM和未解物理的亚网格模型。这是不幸的，因为，小尺度和大尺度都很重要：恒星形成和恒星反馈发生在亚PC尺度上，甚至更小。在全球尺度上，星系嵌入其宇宙环境中：大多数星系不是孤立的，而是以星系团或星系团的形式存在，星系团内充满了炎热、稀薄的星系团内介质(ICM)。这对星系的ISM施加了静态和冲击波压力，其大小与ISM压力相当。因此，ISM响应于集群环境。我们提出了ISM的两个主要步骤：(I)研究了ISM与集群环境的ICM的耦合。(2)为此目的，我们将银河系范围内的ISM模拟与KPC大小的ISM体积的模拟相结合，将其分解为亚PC尺度。因此，我们使用独特的集群环境来获得对ISM中的物理流程的新见解。

The space between the stars inside galaxies is filled by the interstellar medium (ISM), whose evolution is that of a multi-phase, compressible, magnetised and turbulent medium. Its complex and non-linear physics involve a huge range of spatial and temporal scales. Limits in computational power still force us to a make choice: either to study small ISM volumes at sub-pc resolution, or the global ISM of a galaxy with ~ 50 pc resolution and subgrid models for unresolved physics. This is unfortunate, because, both, small and large scales are important: Star formation and stellar feedback occur on sub-pc scales or even smaller. On the global scale, galaxies are embedded in their cosmic environment: most galaxies are not isolated but reside in galaxy groups or clusters, which are filled with a hot, tenuous intra-cluster medium (ICM). This exerts static and ram pressures onto the galaxies’ ISM, with a magnitude comparable to ISM pressures. Consequently, the ISM responds to the cluster environment.We propose two major steps towards an integrated view of the ISM: (i) We study the coupling of the ISM to the ICM of the cluster environment. (ii) For this purpose, we combine ISM simulations on a galaxy-wide scale with simulations of a kpc-size volume of ISM resolved down to sub-pc scales. Thus, we use the unique cluster environment to get new insights into the physical processes in the ISM.