标题： 高红移 0.6 $<$ z $\leq$ 1.0 大质量宁静星系和恒星形成星系的速度弥散函数 显示英文标题

标题： The Velocity Dispersion Function for Massive Quiescent and Star-Forming Galaxies at 0.6 $<$ z $\leq$ 1.0

摘要： 我们展示了首个对大质量宁静和恒星形成星系的恒星速度弥散函数（VDF）的直接光谱测量，这些星系位于$0.6 < z \leq 1.0$。 为了进行此分析，我们使用了来自公开的大型早期星系天体物理学普查（LEGA-C）调查的高信噪比光谱的恒星速度弥散个体测量值。 我们报告了在该红移范围内，无论是宁静星系还是恒星形成星系的VDF都表现出显著的稳定性，尽管我们注意到恒星形成星系的数量密度存在弱演化。 我们将这两个VDF与之前在本地和中间红移处的直接和推断测量值进行了比较，需要注意的是，对于恒星形成星系的VDF，所有时期的先前测量值均未受到良好约束。 我们强调，这项工作首次直接扩展到低恒星速度弥散（$\sigma_\star > 100$ km s$^{-1}$），并延伸至恒星形成星系。 我们在很大程度上与从BOSS测得的高sigma尾部一致，并且我们发现从LEGA-C的中位红移$z\sim0.8$到现在，VDF保持恒定。 显示英文摘要

摘要： We present the first direct spectroscopic measurement of the stellar velocity dispersion function (VDF) for massive quiescent and star-forming galaxies at $0.6 < z \leq 1.0$. For this analysis we use individual measurements of stellar velocity dispersion from high-S/N spectra from the public Large Early Galaxy Astrophysics Census (LEGA-C) survey. We report a remarkable stability of the VDF for both quiescent and star-forming galaxies within this redshift range, though we note the presence of weak evolution in the number densities of star-forming galaxies. We compare both VDFs with previous direct and inferred measurements at local and intermediate redshifts, with the caveat that previous measurements of the VDF for star-forming galaxies are poorly constrained at all epochs. We emphasize that this work is the first to directly push to low-stellar velocity dispersion ($\sigma_\star > 100$ km s$^{-1}$) and extend to star-forming galaxies. We are largely consistent with the high-sigma tail measured from BOSS, and we find that the VDF remains constant from the median redshift of LEGA-C, $z\sim0.8$, to the present day.