论文标题
XGASS：冷气含量和淬火星系下方的星系下方形成主序列
xGASS: Cold gas content and quenching in galaxies below the star forming main sequence
论文作者
论文摘要
我们使用HI和H2全球气体测量值对XGASS和XCOLD GASS的星系进行研究，以研究恒星形成主序列（SFM）下方星系的淬火路径。我们表明，SFM下方的星系人群与HI和H2气体分数比例关系低于HI和H2气体分数关系的星系群体并不是1：1。 SFM下方的过渡区（TZ）1- sigma中的一些星系可能与SFM中的富富富含，并且平均具有更长的气体耗尽时间标准。我们发现了卫星环境淬火的证据，但是TZ中的中央星系反抗简单的淬火途径。这些所谓的“淬火”星系中的一些可能仍然有大量的天然气库，并且不太可能很快耗尽它们。因此，仅用SFR（或其他光学可观察物）来推断出正确的星系淬火模型，但必须包括对冷气的观察。我们还发现，内部结构（尤其是老年和年轻恒星种群的空间分布）在调节气体富含气体富含气体的孤立的TZ星系的恒星形成中起着重要作用，这表明凸起的重要性在其进化中的重要性。
We use HI and H2 global gas measurements of galaxies from xGASS and xCOLD GASS to investigate quenching paths of galaxies below the star formation main sequence (SFMS). We show that the population of galaxies below the SFMS is not a 1:1 match with the population of galaxies below the HI and H2 gas fraction scaling relations. Some galaxies in the transition zone (TZ) 1-sigma below the SFMS can be as HI-rich as those in the SFMS, and have on average longer gas depletion timescales. We find evidence for environmental quenching of satellites, but central galaxies in the TZ defy simple quenching pathways. Some of these so-called "quenched" galaxies may still have significant gas reservoirs and be unlikely to deplete them anytime soon. As such, a correct model of galaxy quenching cannot be inferred with SFR (or other optical observables) alone, but must include observations of the cold gas. We also find that internal structure (particularly, the spatial distribution of old and young stellar populations) plays a significant role in regulating the star formation of gas-rich isolated TZ galaxies, suggesting the importance of bulges in their evolution.
