DYNAMO – II. Coupled stellar and ionized-gas kinematics in two low-redshift clumpy discs
DYNAMO – II. Coupled stellar and ionized-gas kinematics in two low-redshift clumpy discs
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DYNAMO – II. 两个低红移块状盘中的耦合恒星和电离气体运动学
DOI：
10.1093/mnras/stu1029
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发表时间：
2014
影响因子：
4.8
通讯作者：
P. Mcgregor
中科院分区：
文献类型：
--
作者：
R. Bassett;K. Glazebrook;D. Fisher;A. Green;E. Wisnioski;D. Obreschkow;E. Cooper;R. Abraham;I. Damjanov;P. Mcgregor
从新组装的大质量天体(DYNMO)的大动力学样本出发，研究了z⇠为0.1时的两个恒星形成星系的空间分辨恒星运动学。这些星系以高水平的恒星形成和大的电离气体速度弥散为特征，被认为可能类似于高红移的块状圆盘。它们是在双子座天文台使用GMOS仪器以积分场光谱模式进行观测的，具有高光谱分辨率(R‘5400，在观测波长上相当于’24公里S一号‘)和⇠6小时曝光时间，以便通过吸收线测量分辨的恒星运动学。我们还获得了比以前观测到的更高质量的发射线运动学。1.2kpc的空间分辨率足以表明，这些星系中的电离气体(由氢发射跟踪)在形态上是不规则的，形成了多个巨团，而恒星连续谱的光是平滑的，可以用指数分布很好地描述。来自哈勃太空望远镜的互补窄带H↵成像证实了在迭代函数系统数据中观察到的块状气体形态。恒星和电离气体之间的形态差异没有动态地反映出来，因为恒星运动学与电离气体的运动学密切耦合：这两个分量都是平稳旋转的，速度弥散很大(⇠40 KM S 1)，这表明高的气体弥散主要不是由恒星形成反馈驱动的。此外，这些星系的恒星群年龄估计相当年轻(60-500 Myr)。对这些年轻恒星测量的大速度色散表明，我们正在看到厚盘和/或恒星凸起的形成，这支持了最近的模型，这些模型是从高红移的块状星系产生的。
We study the spatially resolved stellar kinematics of two star-forming galaxies at z ⇠ 0.1 from the larger DYnamics of Newly Assembled Massive Objects (DYNAMO) sample. These galaxies, which have been characterized by high levels of star formation and large ionized gas velocity dispersions, are considered possible analogs to high-redshift clumpy disks. They were observed using the GMOS instrument in integral field spectroscopy (IFS) mode at the Gemini Observatory with high spectral resolution (R'5400, equivalent to '24 km s 1 at the observed wavelengths) and ⇠ 6 hour exposure times in order to measure the resolved stellar kinematics via absorption lines. We also obtain higher-quality emission line kinematics than previous observations. The spatial resolution (1.2 kpc) is sucient to show that the ionized gas in these galaxies (as traced by H emission) is morphologically irregular, forming multiple giant clumps while stellar continuum light is smooth and well described by an exponential profile. Clumpy gas morphologies observed in IFS data are confirmed by complementary narrow band H↵ imaging from the Hubble Space Telescope. Morphological di↵erences between the stars and ionized gas are not reflected dynamically as stellar kinematics are found the be closely coupled to the kinematics of the ionized gas: both components are smoothly rotating with large velocity dispersions (⇠ 40 km s 1 ) suggesting that the high gas dispersions are not primarily driven by star-formation feedback. In addition, the stellar population ages of these galaxies are estimated to be quite young (60-500 Myr). The large velocity dispersions measured for these young stars suggest that we are seeing the formation of thick disks and/or stellar bulges in support of recent models which produce these from clumpy galaxies at high redshift.
DOI：
10.1088/0004-637x/768/1/74
发表时间：
2012-11
期刊：
The Astrophysical Journal
影响因子：
--
作者：
L. Tacconi;R. Neri;R. Genzel;F. Combes;A. Bolatto;M. Cooper;S. Wuyts;F. Bournaud;A. Burkert-
通讯作者：
L. Tacconi;R. Neri;R. Genzel;F. Combes;A. Bolatto;M. Cooper;S. Wuyts;F. Bournaud;A. Burkert-
DOI：
10.1088/0004-637x/739/1/45
发表时间：
2011-04
期刊：
The Astrophysical Journal
影响因子：
--
作者：
N. F. Schreiber;A. Shapley;R. Genzel;N. Bouché;G. Cresci;R. Davies;D. Erb;S. Genel;D. Lutz
通讯作者：
N. F. Schreiber;A. Shapley;R. Genzel;N. Bouché;G. Cresci;R. Davies;D. Erb;S. Genel;D. Lutz