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arXiv · 2411.08485

The circumgalactic medium traced by Mg II absorption with DESI: dependence on galaxy stellar mass, star formation rate and azimuthal angle

Zeyu Chen·Enci Wang·Hu Zou·Siwei Zou·Yang Gao·Huiyuan Wang·Haoran Yu·Cheng Jia·Haixin Li·Chengyu Ma·Yao Yao·Weiyu Ding·Runyu Zhu
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Abstract

Understanding the circumgalactic medium (CGM) distribution of galaxies is the key to revealing the dynamical exchange of materials between galaxies and their surroundings. In this work, we use DESI EDR dataset to investigate the cool CGM of galaxies ($0.3 10.0$, the EW(Mg II) at the minor axis is largely suppressed with respect to low mass galaxies. This suggests that the competing processes, such as stellar feedback and gravity, play a key role in shaping the distribution of outflowing gas.

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Zeyu Chen, Enci Wang, Hu Zou, Siwei Zou, Yang Gao, Huiyuan Wang, Haoran Yu, Cheng Jia, Haixin Li, Chengyu Ma, Yao Yao, Weiyu Ding, Runyu Zhu. 2024-11-13. The circumgalactic medium traced by Mg II absorption with DESI: dependence on galaxy stellar mass, star formation rate and azimuthal angle. https://arxiv.org/abs/2411.08485

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