Galaxy clusters are extremely over dense regions of the universe and are therefore ideal for testing how galaxy properties vary with environment. We analyze a sample of >3000 galaxy spectra from 100 galaxy cluster fields, and examine trends in redshift, Dn4000, and a formulated in-fall proxy for member and non-member galaxies. The 4000 Å break (Dn4000) reveals information about the age of each galaxy, and the product of the normalized peculiar velocity and the normalized projected radius of each cluster galaxy serves as a proxy for in-fall time, or how recently each galaxy became gravitationally bound to its cluster. We see a relationship between Dn4000 and the in-fall proxy, with more recently in-fallen galaxies being systematically younger; we interpret this trend as the effect of environmental quenching of cluster galaxies. Furthermore, we see a trend in which all cluster galaxies become older with decreasing redshift, independent of in-fall proxy.

星系团位于宇宙中极其密集的区域，因此非常适合测试星系属性如何随环境变化。我们分析了来自 100 个星系团场的 >3000 个星系光谱样本，并检查了红移趋势、Dn 4000 以及成员星系和非成员星系的公式化秋季代理。4000 Å 断裂 ( Dn 4000) 揭示了关于每个星系年龄的信息，并且每个星系团的归一化特殊速度和归一化投影半径的乘积用作下降时间的代理，或者每个星系最近变成引力束缚在它的星团上。我们看到Dn之间的关系4000 和坠落代理，最近坠落的星系系统地更年轻；我们将这种趋势解释为簇星系环境淬灭的影响。此外，我们看到了一种趋势，即所有星团星系都随着红移的减少而变老，与秋季代理无关。