MUSE-ALMA Haloes – VIII. Statistical study of circumgalactic medium gas
MUSE-ALMA Haloes – VIII. Statistical study of circumgalactic medium gas
复制标题
缪斯-阿尔玛光环 – VIII。
DOI：
10.1093/mnras/stac3497
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发表时间：
2022
影响因子：
4.8
通讯作者：
Sadler, E. M.
中科院分区：
文献类型：
--
作者：
Weng, S.;Péroux, C.;Karki, A.;Augustin, R.;Kulkarni, V. P.;Szakacs, R.;Zwaan, M. A.;Klitsch, A.;Hamanowicz, A.;Sadler, E. M.
气体和金属在环星系介质(CGM)中的分布对星系的演化起着至关重要的作用。MUSE-ALMA光晕观测结合了MUSE、ALMA和HST观测，以限制CGM中多相气体的性质，以及与探测到的吸收气体相关的星系。本文分析了32个强Ly-α吸收体在红移0.2≲z≲1.4时的性质。我们在19个缪斯场的吸收体的±500kms−1范围内探测到79个星系。这些关联星系被发现在距离5.7kpc的物理距离处，恒星形成率低至0.1M⊙yr−1。大量的关联星系使我们能够绘制出它们在Δ范德布面上的物理分布。在前人研究的基础上，我们研究了这些伴生星系的物理和星云性质，并发现：(I)27/32的吸收星系有对应的星系，超过50%的 有两个或更多的伴生星系，(Ii)吸收体柱密度与最近星系的碰撞参数(由维里半径标度)成反相关，正如模拟所预期的那样；(Iii)缔合星系的金属丰度通常比吸光星系的金属丰度大，后者在较大的碰撞参数下降低。很明显，虽然强大的吸波体通常与不止一个星系有关，但我们可以用它们来统计地绘制CGM中气体和金属的分布。
The distribution of gas and metals in the circumgalactic medium (CGM) plays a critical role in how galaxies evolve. The MUSE-ALMA Haloes survey combines MUSE, ALMA, and HST observations to constrain the properties of the multiphase gas in the CGM and the galaxies associated with the gas probed in absorption. In this paper, we analyse the properties of galaxies associated with 32 strong ${\rm H\, {\small I}}$ Ly-α absorbers at redshift 0.2 ≲z≲ 1.4. We detect 79 galaxies within ±500 kms−1of the absorbers in our 19 MUSE fields. These associated galaxies are found at physical distances from 5.7 kpc and reach star formation rates as low as 0.1 M⊙yr−1. The significant number of associated galaxies allows us to map their physical distribution on the Δvandbplane. Building on previous studies, we examine the physical and nebular properties of these associated galaxies and find the following: (i) 27/32 absorbers have galaxy counterparts and more than 50 per cent of the absorbers have two or more associated galaxies, (ii) the ${\rm H\, {\small I}}$ column density of absorbers is anticorrelated with the impact parameter (scaled by virial radius) of the nearest galaxy as expected from simulations, (iii) the metallicity of associated galaxies is typically larger than the absorber metallicity, which decreases at larger impact parameters. It becomes clear that while strong ${\rm H\, {\small I}}$ absorbers are typically associated with more than a single galaxy, we can use them to statistically map the gas and metal distribution in the CGM.