Extreme gas kinematics in an off-nuclear HII region of SDSS J143245.98+404300.3
Extreme gas kinematics in an off-nuclear HII region of SDSS J143245.98+404300.3
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SDSS J143245.98 404300.3 非核 HII 区域的极端气体运动学
DOI：
10.1051/0004-6361/201936140
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发表时间：
2019
影响因子：
6.5
通讯作者：
J. Vílchez
中科院分区：
文献类型：
--
作者：
B. R. D. Pino;S. Arribas;Javier Piqueras López;A. C. Gómez;J. Vílchez
我们提出并讨论了最近报道的位于SDSS J143245.98+404300.3核外0.8 - 1.0 kpc的离核HII区中具有极端运动学的电离气体组分的性质。通过在Hα谱线上探测到非常宽的发射翼来识别高速气体成分，半高宽（FWHM）≥ 850−1000 km s−1。 这样的气体运动学与其他HII区域相比是非常高的，并且与z = 2的一些恒星形成星系团的报告相似。 空间分辨分析表明，高速气体至少延伸到1.90秒差距，它可能与电离的外流相兼容，后者携带的气体的速度比气体转化为恒星的速度快7到9倍。我们在其他发射谱线中没有探测到宽的发射翼，例如Hβ，这可能是由于中等的尘埃消光，也没有在[N II]λλ6548，6584或[S II]λλ6717，6731中探测到宽的发射翼，这可能是由于存在由快速流动的风的影响引起的湍流混合层。缺乏与沃尔夫-拉叶星相关的光谱特征表明，来自大量大质量恒星和/或超新星的恒星风可能是驱动高速气体的机制。
We present and discuss the properties of an ionized gas component with extreme kinematics in a recently reported off-nuclear HII region located at ∼0.8−1.0 kpc from the nucleus of SDSS J143245.98+404300.3. The high-velocity-gas component is identified by the detection of very broad emission wings in the Hα line, with full width at half maximum (FWHM) ≥ 850−1000 km s−1. Such gas kinematics are outstandingly high compared to other HII regions in local galaxies and are similar to those reported in some star-forming clumps of galaxies at z ∼ 2. The spatially resolved analysis indicates that the high-velocity gas extends at least ∼90 pc and it could be compatible with an ionized outflow entraining gas at a rate between approximately seven and nine times faster than the rate at which gas is being converted into stars. We do not detect broad emission wings in other emission lines such as Hβ, perhaps due to moderate dust extinction, nor in [N II]λλ6548, 6584 or [S II]λλ6717, 6731, which could be due to the presence of turbulent mixing layers originated by the impact of fast-flowing winds. The lack of spectral signatures associated to the presence of Wolf–Rayet stars points towards stellar winds from a large number of massive stars and/or supernovae as the likely mechanisms driving the high-velocity gas.
影响因子：
4.9
作者：
Bundy, Kevin;Bershady, Matthew A.;Zhang, Kai
通讯作者：
Zhang, Kai
低z发光恒星形成星系的电离气体流出和整体运动学
DOI：
10.1017/s174392131400934x
发表时间：
2015
期刊：
Proceedings of the International Astronomical Union
影响因子：
--
作者：
Arribas S
通讯作者：
Arribas S