The KMOS Redshift One Spectroscopic Survey (KROSS) : rotational velocities and angular momentum of z ≈ 0.9 galaxies.
The KMOS Redshift One Spectroscopic Survey (KROSS) : rotational velocities and angular momentum of z ≈ 0.9 galaxies.
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DOI：
10.1093/mnras/stx217
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发表时间：
2017-01
影响因子：
4.8
通讯作者：
C. Harrison;C. Harrison;H. Johnson;A. M. Swinbank;J. Stott;J. Stott;R. Bower;I. Smail;A. T
中科院分区：
文献类型：
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作者：
C. Harrison;C. Harrison;H. Johnson;A. M. Swinbank;J. Stott;J. Stott;R. Bower;I. Smail;A. T
本文介绍了KMOS（K波段多目标摄谱仪）红移一号光谱巡天（KROSS）对586个H-α星系的动力学测量结果。样本代表了在这个红移（z=0.6-1.0）的典型恒星形成星系，星星形成率的中位数为7 Msol/yr，恒星质量范围为log[M/Msol]~9-11。我们发现，对于我们的旋转主导源（v/sigma>1），旋转速度-恒星质量关系（塔利-费舍尔关系的逆）具有与z=0圆盘观察到的一致的斜率和归一化。相比之下，比角动量（j;角动量除以恒星质量）平均比z=0的圆盘低约0.2-0.3 dex。比角动量标度为M^[0.6+/-0.2]，与暗物质的预期一致（即，与M^[2/3]成比例）。我们发现z~0.9的恒星形成星系的比角动量随着Sersic指数的增加而减小。从视觉上看，对于给定的质量，具有最高比角动量的源具有最多的盘主导形态。这意味着角动量-质量-形态的关系，类似于在本地大质量星系中观察到的，已经在z~1的位置。
We present dynamical measurements for 586 H-alpha detected star-forming galaxies from the KMOS (K-band Multi-Object Spectrograph) Redshift One Spectroscopic Survey (KROSS). The sample represents typical star-forming galaxies at this redshift (z=0.6-1.0), with a median star formation rate of ~7 Msol/yr and a stellar mass range of log[M/Msol]~9-11. We find that the rotation velocity-stellar mass relationship (the inverse of the Tully-Fisher relationship) for our rotationally-dominated sources (v/sigma>1) has a consistent slope and normalisation as that observed for z=0 disks. In contrast, the specific angular momentum (j; angular momentum divided by stellar mass), is ~0.2-0.3 dex lower on average compared to z=0 disks. The specific angular momentum scales as M^[0.6+/-0.2], consistent with that expected for dark matter (i.e., proportional to M^[2/3]). We find that z~0.9 star-forming galaxies have decreasing specific angular momentum with increasing Sersic index. Visually, the sources with the highest specific angular momentum, for a given mass, have the most disk-dominated morphologies. This implies that an angular momentum-mass-morphology relationship, similar to that observed in local massive galaxies, is already in place by z~1.