We employ high-resolution cosmological zoom-in simulations focusing on a high-sigma peak and an average cosmological field at $z\sim 6-12$, in order to investigate the influence of environment and baryonic feedback on galaxy evolution in the reionization epoch. Strong feedback, e.g., galactic winds, caused by elevated star formation rates (SFRs) is expected to play an important role in this evolution. We compare different outflow prescriptions: (i) constant wind velocity (CW), (ii) variable wind scaling with galaxy properties (VW), and (iii) no outflows (NW). The overdensity leads to accelerated evolution of dark matter and baryonic structures, absent in the "normal" region, and to shallow galaxy stellar mass functions at the low-mass end. Although CW shows little dependence on both environments, the more physically motivated VW model does exhibit this effect. In addition, VW can reproduce the observed specific SFR (sSFR) and the sSFR-stellar mass relation, which CW and NW fail to satisfy simultaneously. Winds also differ substantially in affecting the state of the intergalactic medium (IGM). The difference lies in volume-filling factor of hot, high-metallicity gas which is near unity for CW, while it remains confined in massive filaments for VW, and locked up in galaxies for NW. Such gas is nearly absent in the normal region. Although all wind models suffer from deficiencies, the VW model seems to be promising in correlating the outflow properties to those of host galaxies. Further constraints on the state of the IGM at high-$z$ are needed to separate different wind models.
CAMELS Environments: The Impact of Local Neighbours on Galaxy Evolution across the SIMBA, IllustrisTNG, ASTRID, and Swift-EAGLE Simulations
University of Connecticut（康涅狄格大学）；Korea Institute for Advanced Study（韩国高等研究院）；Yale University（耶鲁大学）；University of Michigan（密歇根大学）；University of Cambridge（剑桥大学）；Flatiron Institute（平顿研究所）
Testing the Strong Equivalence Principle. II. Relating the External Field Effect in Galaxy Rotation Curves to the Large-Scale Structure of the Universe
The Missing Baryons in the Milky Way and Local Group
银河系和所有其他星系都缺少大部分重子，因为已知的重子质量与引力质量之比（维里半径内）比WMAP确定的宇宙比小好几倍。这意味着要么重子从未落入星系，要么是强大的星系风带走了大部分重子。如果我们能够发现缺失的重子并测量其性质：空间分布、温度和金属丰度，就有可能区分这两种途径。星系中缺失的重子预计温度为1- 3E 6 K，因此需要X射线观测。在这篇白皮书中，我们展示了如何使用IXO等设备获得X射线观测，以识别和研究这些难以捉摸的重子。
The assembly and fate of a giant disc galaxy in a protocluster at $z = 3$
Kapteyn Astronomical Institute, University of Groningen（格罗宁根大学卡普坦天文研究所）；Leiden Observatory, Leiden University（莱顿大学莱登天文台）；Dipartimento di Fisica e Astronomia "Augusto Righi", Alma Mater Studiorum Università di Bologna（博洛尼亚大学物理与天文学系）；INAF-Osservatorio di Astrofisica e Scienza dello Spazio di Bologna（博洛尼亚空间科学与天体物理观测站）；INFN-Sezione di Bologna（博洛尼亚意大利国家核物理研究所）
Interpreting Cosmological Information from Neural Networks in the Hydrodynamic Universe
Foundation for Research and Technology—Hellas（希腊研究与技术基金会）；Department of Physics, University of Crete（克里特大学物理系）；Department of Astrophysical Sciences, Princeton University（普林斯顿大学天体物理学系）；Center for Computational Astrophysics, Flatiron Institute（平托研究所计算天体物理中心）
A New Window into the Baryon Cycle at Cosmic Noon with Line Intensity Mapping: Forecasts for auto- and cross-correlations in [CII]-158$μ$m, HI 21 cm, CO$_{J+1\rightarrow J}$, and H$α$ galaxies
University of Pennsylvania（宾夕法尼亚大学）；University of California, Los Angeles（加州大学洛杉矶分校）；California Institute of Technology（加州理工学院）；Max-Planck-Institut für Astronomie（马克斯·普朗克天文学研究所）；Jet Propulsion Laboratory, California Institute of Technology（加州理工学院喷气推进实验室）；University of Illinois Urbana-Champaign（伊利诺伊大学厄巴纳-香槟分校）；University of Virginia（弗吉尼亚大学）
The Enrichment of the Intergalactic Medium with Adiabatic Feedback I: Metal Cooling and Metal Diffusion
采用金属冷却、金属湍流扩散和热能，利用一系列SPH模拟研究IGM金属富集。采用绝热反馈机制，防止气体冷却，产生没有明确的风粒子的星系风。模拟产生的宇宙恒星形成历史（SFH）与观测结果大致一致，直到z $\sim$ 0.5，以及通用中性氢分数（$Ω_{\rm H I}$）的稳定演变。在z=0时，大约40%的重子在温暖的星系际介质（WHIM）中，但大多数金属（80%-90%）被锁定在恒星中。在较高的z，IGM中的金属比例较高，这是由于星系更有效的损失。在整个宇宙历史中，IGM金属主要存在于WHIM。星系内部气体的金属丰度演化与观测结果基本一致，但弥散IGM在z $\sim$ 2.5处富集。银河风最有效地富集了中等质量范围$10^{10}$ M $_{\sun}$ - $10^{11}$ M $_{\sun}$的晕的IGM。在低质量端气体被阻止吸积到晕上，并且具有非常低的金属丰度。在高质量端，随着星系中恒星质量分数的降低，晕重子逃逸率也随之降低。这可能是因为恒星形成活动和逃逸效率的降低。金属增强冷却，使WHIM气体冷却到星系上，并增加恒星的形成。金属的扩散使得风在逃逸之前混合，减少了IGM的金属含量，有利于星系晕内的气体和恒星形成气体。扩散显著增加了低金属丰度气体的量，并改变了密度-金属丰度关系。
