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arXiv 1806.04142astro-ph.GA
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红移z ~ 2处环境猝灭的证据

Evidence of Environmental Quenching at Redshift z ~ 2

Zhiyuan Ji, Mauro Giavalisco, Christina C. Williams, Sandra M. Faber, Henry C. Ferguson, Yicheng Guo, Teng Liu, Bomee Lee

摘要:

我们报告的证据,环境淬火星系之间的红移~ 2,即一个星系淬火其恒星形成活动的概率是在其他淬火,更大质量的星系附近的空间区域增强。这种效应被观察到,在角尺度θ< 20 arcsec时,静止星系围绕着静止星系形成强的集群,对应于z = 2时168(502)kpc的适当(同动)尺度。这种效应只在其他静止星系周围的静止星系中观察到;在静止星系周围或在恒星形成星系周围发现恒星形成星系的概率与相同质量和相同红移的星系的聚集强度一致,正如在星系聚集的专门研究中所观察到的那样。这种效应与质量有关,即质量较小的星系($\rm{M_*<10^{10} Msun}$)的猝灭概率比质量较大的星系更强,也就是说,它与质量相对于引力星系团簇的趋势相反。观察到这种效应的空间尺度表明,这些环境是巨大的晕,在这种情况下,观察到的效应可能是卫星淬火。这种效应也与红移有关,因为在z = 1.6时,静止星系围绕其他静止星系的聚集强度比z = 2.6时具有相同恒星质量的星系大1.7倍。这种红移的依赖性允许一个粗略的估计的时间尺度的环境淬火的低质量星系,这是在1.5 - 4 Gyr的范围内,在广泛的协议与其他估计和我们的想法卫星淬火。

英文摘要:

We report evidence of environmental quenching among galaxies at redshift ~ 2, namely the probability that a galaxy quenches its star formation activity is enhanced in the regions of space in proximity of other quenched, more massive galaxies. The effect is observed as strong clustering of quiescent galaxies around quiescent galaxies on angular scales θ< 20 arcsec, corresponding to a proper(comoving) scale of 168 (502) kpc at z = 2. The effect is observed only for quiescent galaxies around other quiescent galaxies; the probability to find star-forming galaxies around quiescent or around star-forming ones is consistent with the clustering strength of galaxies of the same mass and at the same redshift, as observed in dedicated studies of galaxy clustering. The effect is mass dependent in the sense that the quenching probability is stronger for galaxies of smaller mass ($\rm{M_*<10^{10} Msun}$) than for more massive ones, i.e. it follows the opposite trend with mass relative to gravitational galaxy clustering. The spatial scale where the effect is observed suggests these environments are massive halos, in which case the observed effect would likely be satellite quenching. The effect is also redshift dependent in that the clustering strength of quiescent galaxies around other quiescent galaxies at z = 1.6 is ~ 1.7 times larger than that of the galaxies with the same stellar mass at z = 2.6. This redshift dependence allows for a crude estimate of the time scale of environmental quenching of low-mass galaxies, which is in the range 1.5 - 4 Gyr, in broad agreement with other estimates and with our ideas on satellite quenching.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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