The morphology-density relation, ram-pressure stripping and ultra-diffuse galaxies in extra high resolution galaxy cluster zoom-in simulations

近年来，星系团及其通过恒星形成减少（即淬火）对单个卫星星系的影响一直是广泛观测研究的焦点。 由于所有的卫星星系都是在星系团中加工的，因此有机会研究星系演化的环境依赖性。这个建议的主要目标是了解以下问题：如何以及在何种程度上冲压压力剥离星系团有助于建立的形态密度关系（环境密度和形态星系类型之间的观测关系）？这与建议的第二个重点密切相关，即评价和衡量星系团中的环境淬灭机制。这反过来又与第三个问题有关：最近发现的超漫射星系（UDG）形成的星系团中可能的演化途径是什么？为了理解这些联系，我们将根据宇宙流体动力学模拟集\textit{Magneticum Pathfinder}使用的物理过程的处理进行极高分辨率的放大模拟，该模拟集已被证明成功再现了星系和星系团的各种属性。我们的目标是以前所未有的细节水平解决冲压压力剥离和UDG的形成机制。为此，我们的目标是模拟24个星系团的晕质量M_halo > 1 e15 M_sol，解决了近1 e9粒子的维里半径内，给出了暗物质粒子质量的m_dm~ 4 e6 M_sol/h和气体粒子质量的$m_gas ~ 7 e5 M_sol/h，从而在空间分辨率的星星粒子~240 pc/h。有了建议的极高分辨率，我们将能够在空间上解决所有必要的物理过程（特别是湍流混合）参与卫星星系淬火和UDG的形成。此外，我们还计划将至少一个集群的分辨率提高到质量分辨率的10倍，将空间分辨率提高到~100 pc/h。因此，这个项目提供了一个独特的机会，可以深刻地增加我们对星系团如何转变其卫星星系的理解。

Galaxy clusters and their impact via star-formation reduction, i.e. quenching, on individual satellite galaxies has been the focus of extensive observational research in recent years. As all satellite galaxies are processed in galaxy clusters, an opportunity arises to study the environmental dependence of galaxy evolution. The primary goal of this proposal is to understand the following question: How and to what extent does ram-pressure stripping in galaxy clusters contribute to the build-up of the morphology-density relation (an observational relation between environmental density and morphological galaxy type)? This is closely related to the second focus of the proposal, namely the evaluation and weighting of environmental quenching mechanisms in galaxy clusters. This, in turn, is connected to a third question: What are possible evolutionary pathways in galaxy clusters for the formation of the recently discovered ultra-diffuse galaxies (UDGs)? To understand these connections, we will perform extremely high resolution zoom-in simulations based on the treatment of physical processes used for the cosmological hydrodynamical simulation set \textit{Magneticum Pathfinder}, which have proven to successfully reproduce various properties of galaxies and galaxy clusters. Our dedicated goal is to resolve both ram-pressure stripping and the formation mechanism(s) of UDGs with an unprecedented level of detail. To this end, we aim at simulating 24 galaxy clusters with halo mass M_halo > 1e15 M_sol, resolved with almost 1e9 particles within the virial radius, giving a dark matter particle mass of m_dm~4e6 M_sol/h and a gas particle mass of $m_gas ~ 7e5 M_sol/h, resulting in a spatial resolution of the star particles of ~240 pc/h. With the proposed extreme high resolution we will be able to spatially resolve all necessary physical processes (especially turbulent mixing) involved in satellite galaxy quenching and UDG formation. In addition, we also plan to push the resolution for at least one cluster to ten times better mass resolution, increasing the spacial resolution to ~100 pc/h. As such, this project offers the unique opportunity to profoundly increase our understanding of how galaxy clusters transform their satellite galaxies.