Metal-enriched halo gas across galaxy overdensities over the last 10 billion years
Metal-enriched halo gas across galaxy overdensities over the last 10 billion years
复制标题
过去 100 亿年星系中富含金属的晕气体密度过高
DOI：
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发表时间：
2021
影响因子：
4.8
通讯作者：
T. Theuns
中科院分区：
文献类型：
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作者：
Xavier Battaia;Fabrizio Arrigoni;R. Dutta;M. Fumagalli;M. Fossati;R. Bielby;J. Stott;E. Lofthouse;S. Cantalupo;F. Cullen;R. Crain;T. Tripp;J. Prochaska;F. A. Battaia;J. Burchett;J. Fynbo;M. Murphy;J. Schaye;N. Tejos;T. Theuns
在星系周围气体的MUSE分析调查和类星体视线和星系演化调查中，我们研究了富含金属的光环气体，这些气体在z < 2处被Mg ii和C iv吸收。利用这些在类星体场中进行的大型和完整的星系调查，我们研究了金属分布对星系性质和超密度的依赖，直至物理投影间隔为750kpc。我们发现，在整个探测红移范围内，低温、低电离气体受到环境的显著影响，在较高的过密度群环境中，以及在总体恒星质量和恒星形成速率较大的区域，Mg ii的吸收率约为2 - 3倍。与这些结果相补充的是，我们进一步研究了由C iv吸收追踪到的高电离气体，发现它可能比Mg ii气体更延伸，在给定距离上的覆盖分数约为2倍。我们发现，与Mg ii吸收相比，C iv吸收的强度和覆盖分数对星系性质和环境的依赖性较小，但更大质量和恒星形成星系的C iv吸收发生率也高达约2倍。随着红移的增加，病毒半径内Mg和civ的吸收率呈暂时性的增加，在z > 1处分别增加了≈1.5和≈4倍。从我们的结果中可以清楚地看出，环境过程对星系周围金属的分布有重大影响，在分析气体晕和星系特性之间的相关性时需要充分考虑。
We present a study of metal-enriched halo gas traced by Mg ii and C iv absorption at z < 2 in the MUSE Analysis of Gas around Galaxies survey and the Quasar Sightline and Galaxy Evolution survey. Using these large and complete galaxy surveys in quasar fields, we study the dependence of the metal distribution on galaxy properties and overdensities, out to physical projected separations of 750 kpc. We find that the cool, low-ionization gas is significantly affected by the environment across the full redshift range probed, with ≈2 − 3 times more prevalent and stronger Mg ii absorption in higher overdensity group environments and in regions with greater overall stellar mass and star formation rates. Complementary to these results, we have further investigated the more highly ionized gas as traced by C iv absorption, and found that it is likely to be more extended than the Mg ii gas, with ≈2 times higher covering fraction at a given distance. We find that the strength and covering fraction of C iv absorption show less significant dependence on galaxy properties and environment than the Mg ii absorption, but more massive and star-forming galaxies nevertheless also show ≈2 times higher incidence of C iv absorption. The incidence of Mg ii and C iv absorption within the virial radius shows a tentative increase with redshift, being higher by a factor of ≈1.5 and ≈4, respectively, at z > 1. It is clear from our results that environmental processes have a significant impact on the distribution of metals around galaxies and need to be fully accounted for when analyzing correlations between gaseous haloes and galaxy properties.