发表机构
European Southern Observatory; Max-Planck-Institut für Extraterrestrische Physik (MPE); Swinburne University of Technology; CSIRO Space and Astronomy; Aix Marseille Univ.; CNRS; Laboratoire d’Astrophysique de Marseille; Leibniz-Institut für Astrophysik Potsdam (AIP); Max-Planck-Institut für Astrophysik (MPA); Observatoire Astronomique de Strasbourg（欧洲南方天文台; 马克斯·普朗克地外物理研究所（MPE）; 斯威本科技大学; CSIRO空间与天文学部; 艾克斯-马赛大学; 法国国家科学研究中心; 马赛天体物理实验室; 莱布尼茨波茨坦天体物理研究所（AIP）; 马克斯·普朗克天体物理研究所（MPA）; 斯特拉斯堡天文台）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
该研究通过ALMA观测表征79个z~0.5星系的分子气体，测量质量、运动学和气体分数，以量化分子气体作用、表征气体流动并普查凝聚重子，为重子循环提供见解。
AI 中文摘要
气体与星系之间的相互作用对于我们理解结构形成至关重要。这种重子循环研究的一个基本要素是对星系及其直接环境（即所谓的星系周介质）中凝聚物质（恒星和冷气体）的完整普查。特别重要的是将分子气体转化为恒星的过程，以及判断这种<100K的气体是否示踪了气体流动。MUSE-ALMA 晕巡天项目为79个$z\sim0.5$的星系样本组装了中性原子气体HI、电离气体和恒星成分的探针。这是通过将背景类星体的吸收线光谱与投影撞击参数（低至5 kpc，高达250 kpc）相结合，以探测低密度星系周气体，并使用电离气体和恒星的电离气体发射线示踪剂来实现的。本文介绍了大型计划的观测设置，并发布了表征部分MUSE-ALMA 晕目标分子相的数据，以达到对其凝聚重子的完整普查。ALMA独特的毫米波覆盖范围和高灵敏度非常适合表征这些$z\sim0.5$ HI选择的星系的CO发射。通过测量分子质量、运动学、气体流动和气体分数，该项目随后：i) 量化分子气体在富HI星系中的作用，ii) 通过形态运动学分析表征气体流动的分子相，iii) 建立星际介质和星系周介质中凝聚重子的普查。最终，这些结果将为重子循环——星系形成的关键组成部分——提供独特的见解。
英文摘要
The interactions between gas and galaxies are of paramount importance to our understanding of structure formation. A fundamental element of such baryon cycle studies is a complete census of the condensed matter (stars and cold gas) in both galaxies and their immediate surroundings, the so-called circumgalactic medium. Of particular importance are the processes of converting molecular gas into stars and deciphering whether this <100K gas is tracing gas flows. The MUSE-ALMA Haloes survey has assembled probes of the neutral atomic gas HI, ionised gas and stellar component for a sample of 79 $z\sim0.5$ galaxies. This is achieved by combining absorption line spectroscopy of background quasars with projected impact parameter as low as 5 kpc and up to 250 kpc to probe the low density circumgalactic gas with emission line tracers of both ionised gas and stars. This paper presents the Large Programme observational set-up and releases the data characterising the molecular phase of some of the MUSE-ALMA Haloes targets so as to reach a complete census of their condensed baryons. ALMA's unique millimetre coverage and high sensitivity is ideal to characterise the CO emission of these $z\sim0.5$ HI-selected galaxies. By measuring the molecular mass, kinematics, gas flows and gas fractions, this project then: i) quantifies the role of molecular gas in HI-rich galaxies, ii) characterises the molecular phase of gas flows from morpho-kinematics analyses, and iii) establishes a census of the condensed baryons in the interstellar and circumgalactic media. Ultimately, these results will provide unique insights into the baryon cycle - a crucial component of galaxy formation.
CommentsAccepted for publication in A&A in February 2026. We acknowledge that works relevant to these results have been published since then. Part of the MUSE-ALMA survey series, see simultaneously posted papers by Barfety et al. and O'Beirne et al. The reduced data are available here: https://almascience.eso.org/alma-data/lp/alma-muse/
Journal refAstronomy & Astrophysics, Volume 708, 2026, id.A146, 18 pp
DOI：10.1051/0004-6361/202558645
