论文标题
通过堆叠直接测量Hi-Halo质量关系
Direct Measurement of the HI-Halo Mass Relation through Stacking
论文作者
论文摘要
我们通过堆叠Arecibo Fast Legacy Alfa调查中的整个组的HI光谱，对不同质量的暗物质HI质量中的总HI质量进行准确的测量。光晕是从Sloan Digital Sky Survey DR7 Main Galaxy样品中构建的光学星系组目录中选择的，其可靠测量光环质量和光晕会员资格。我们发现，正如几种理论模型所假定的那样，高halo质量关系不是一个简单的单调函数。除了光晕质量的依赖性外，总的HI气体质量还显示出对光环丰富度的强烈依赖，在固定光晕质量的组中，HI质量较大。此外，组目录中至少有三个成员星系的光环急剧下降，这可能是由于病毒光晕加热和AGN反馈引起的。 HI气体的主要贡献来自$ M <10^{12.5} h^{ - 1} M _ {\ odot} $的HAROS的中央星系，而卫星星系则在更大的晕孔上占主导地位。我们的测量与高富集星系的三相形成方案一致。光滑的冷气积聚正在推动$ M <10^{11.8} h^{ - 1} m _ {\ odot} $的HI质量增长，而后期形成的Halos则具有更多的HI增值。病毒的光环冲击热和AGN反馈将生效，以减少HAROS的HI供应$ 10^{11.8} H^{ - 1} M _ {\ odot} <m <10^{13} h^{ - 1} h^{ - 1} m _ {\ odot} $。 HAROS中的HI质量比$ 10^{13} H^{ - 1} m _ {\ odot} $通常通过合并而增长，而对光环富度的依赖变得较弱。
We present accurate measurements of the total HI mass in dark matter halos of different masses at z ~ 0, by stacking the HI spectra of entire groups from the Arecibo Fast Legacy ALFA Survey. The halos are selected from the optical galaxy group catalog constructed from the Sloan Digital Sky Survey DR7 Main Galaxy sample, with reliable measurements of halo mass and halo membership. We find that the HI-halo mass relation is not a simple monotonic function, as assumed in several theoretical models. In addition to the dependence of halo mass, the total HI gas mass shows strong dependence on the halo richness, with larger HI masses in groups with more members at fixed halo masses. Moreover, halos with at least three member galaxies in the group catalog have a sharp decrease of the HI mass, potentially caused by the virial halo shock-heating and the AGN feedback. The dominant contribution of the HI gas comes from the central galaxies for halos of $M<10^{12.5}h^{-1}M_{\odot}$, while the satellite galaxies dominate over more massive halos. Our measurements are consistent with a three-phase formation scenario of the HI-rich galaxies. The smooth cold gas accretion is driving the HI mass growth in halos of $M<10^{11.8}h^{-1}M_{\odot}$, with late-forming halos having more HI accreted. The virial halo shock-heating and AGN feedback will take effect to reduce the HI supply in halos of $10^{11.8}h^{-1}M_{\odot}<M<10^{13}h^{-1}M_{\odot}$. The HI mass in halos more massive than $10^{13}h^{-1}M_{\odot}$ generally grows by mergers, with the dependence on halo richness becoming much weaker.
