论文标题
观察暗物质积聚与星系生长之间的相关性：I。孤立的银河系星系中最近的恒星形成活性
Observing Correlations Between Dark Matter Accretion and Galaxy Growth: I. Recent Star Formation Activity in Isolated Milky Way-Mass Galaxies
论文作者
论文摘要
新鲜气体积聚到光环与星系星形成之间的相关性对于理解星系形成至关重要。不同的理论模型已经预测了光环积聚率和星系星形成率之间的不同相关强度，从较强的正相关到很少或没有相关性。在这里，我们提出了一种技术，可以在观察上测量这种相关强度，用于$ z <0.123 $的孤立银河系星系。该技术基于暗物质积聚率与相邻星系的预计密度谱之间的相关性。这些相关性也是过去与Splashback Radii一起工作的基础。我们将我们的技术应用于Sloan Digital Sky调查中观察到的星系，以及宇宙中的模拟星系，我们可以在其中测试任何所需的相关强度。我们发现，用$ \ gtrsim 85 \％$置信度排除了暗物质积聚与最近的恒星形成活动之间的正相关。我们的结果表明，恒星形成活性可能与$ z = 0 $的孤立银河系星系的新鲜积聚不相关，而其他过程（例如气体回收利用）则占据了进一步的星系生长。
The correlation between fresh gas accretion onto haloes and galaxy star formation is critical to understanding galaxy formation. Different theoretical models have predicted different correlation strengths between halo accretion rates and galaxy star formation rates, ranging from strong positive correlations to little or no correlation. Here, we present a technique to observationally measure this correlation strength for isolated Milky Way-mass galaxies with $z < 0.123$. This technique is based on correlations between dark matter accretion rates and the projected density profile of neighbouring galaxies; these correlations also underlie past work with splashback radii. We apply our technique to both observed galaxies in the Sloan Digital Sky Survey as well as simulated galaxies in the UniverseMachine where we can test any desired correlation strength. We find that positive correlations between dark matter accretion and recent star formation activity are ruled out with $\gtrsim 85\%$ confidence. Our results suggest that star formation activity may not be correlated with fresh accretion for isolated Milky Way-mass galaxies at $z=0$ and that other processes, such as gas recycling, dominate further galaxy growth.
