论文标题
在Galaxy簇中检测各向异性卫星淬火最高$ z \ sim1 $
Detection of anisotropic satellite quenching in galaxy clusters up to $z\sim1$
论文作者
论文摘要
集群环境中的卫星星系比一般领域的星系更可能被淬灭。最近，据报道，卫星星系淬灭取决于相对于其中央星系的方向：沿着主要中心轴的卫星比沿较小轴的卫星更可能被淬灭。在本文中，我们报告了这种各向异性淬火的检测，该淬火基于由Hyper Soprime-Cam Subaru策略计划构建的大型光学选择的集群目录。我们计算出静态的卫星星系分数，这是从中央星系的主要轴测量的方向角度的函数，发现静态分数为$ 0.25 <z <1 $，是通过正弦函数合理地拟合的，幅度为几百分之几。各向异性在内部区域（$ <r_ \ mathrm {200m} $）群集的群体更清晰，在集群郊区（$> r_ \ mathrm {200m} $）中不显着。我们还确认，观察到的各向异性无法通过沿两个轴的局部星系密度或恒星质量分布的差异来解释。两个轴之间的静态分数过剩表明，导致各向异性的淬灭效率几乎独立于恒星质量，至少至我们的恒星质量极限为$ M _ {*} = 1 \ times10^{10} {10} {10} \ \，m _ {\ odot} $。最后，我们认为观察到的各向异性的物理起源应该比$ \ sim1 \，\ mathrm {gyrm {gyr} $具有较短的淬火时间尺度，就像拉姆压剥离一样，因为为了观察到各向异性淬火，必须在其初始的Orientition Angles Qungers Qungertation Qunece中淬火。
Satellite galaxies in the cluster environment are more likely to be quenched than galaxies in the general field. Recently, it has been reported that satellite galaxy quenching depends on the orientation relative to their central galaxies: satellites along the major axis of centrals are more likely to be quenched than those along the minor axis. In this paper, we report a detection of such anisotropic quenching up to $z\sim1$ based on a large optically-selected cluster catalogue constructed from the Hyper Suprime-Cam Subaru Strategic Program. We calculate the quiescent satellite galaxy fraction as a function of orientation angle measured from the major axis of central galaxies and find that the quiescent fractions at $0.25<z<1$ are reasonably fitted by sinusoidal functions with amplitudes of a few percent. Anisotropy is clearer in inner regions ($<r_\mathrm{200m}$) of clusters and not significant in cluster outskirts ($>r_\mathrm{200m}$). We also confirm that the observed anisotropy cannot be explained by differences in local galaxy density or stellar mass distribution along the two axes. Quiescent fraction excesses between the two axes suggest that the quenching efficiency contributing to the anisotropy is almost independent of stellar mass, at least down to our stellar mass limit of $M_{*}=1\times10^{10}\,M_{\odot}$. Finally, we argue that the physical origins of the observed anisotropy should have shorter quenching timescales than $\sim1\,\mathrm{Gyr}$, like ram-pressure stripping, because, for anisotropic quenching to be observed, satellites must be quenched before their initial orientation angles are significantly changed.
