Kinematic structure of the 30 Doradus giant H II region
Kinematic structure of the 30 Doradus giant H II region
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30 Doradus 巨星 H II 区域的运动结构
DOI：
10.1086/174017
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发表时间：
1994
期刊：
影响因子：
--
通讯作者：
R. Kennicutt
中科院分区：
文献类型：
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作者：
Y. Chu;R. Kennicutt
我们利用塞罗托洛洛美洲天文台（CTIO）4米望远镜上的中阶梯CCD摄谱仪，绘制了剑鱼座30号巨星H II区的星云速度场。30 Dor的运动学非常复杂。外部区域的特征是由一个光滑的速度场，但其湍流速度，30-40公里/秒的半高宽（FWHM），是相当高的比那些在大多数较小的H II区。在中央9分钟的核心，多个速度分量观察到在大多数位置。速度场由大量的膨胀结构主导，其大小从1到100 pc，膨胀速度为20-200 km/s，并且通常组织成大型分层网络。这些复杂的膨胀结构在30 Dor中的积分产生了一个令人惊讶的简单轮廓，具有广泛的高斯核心和微弱的扩展翼。几个快速膨胀的壳层，直径为2-20 pc，膨胀速度为100-300 km/s，动能为0.5-10 x 10（exp 50）尔格。大的快速膨胀的壳层和网络与扩展的X射线源一致，可能与嵌入超壳层中的超新星遗迹有关，这些超新星遗迹是由星风和OB协会的超新星的联合作用产生的。我们已经使用强度校准的阶梯光谱，以确定基本的物理和动力学性质的运动学特征在30度。膨胀的壳层包含了30多尔复合体中大约一半的动能，并且这个能量比该区域的引力结合能高出几倍。气体的能量需求与观测到的30多尔的恒星含量是一致的，如果气体被恒星风和超新星的组合加速。外推目前的能量注入率在整个生命周期的星云OB复杂的建议，30多尔及其附近地区将演变成一个超巨星壳所看到的LMC和其他附近的星系。
We have used the echelle CCD spectrograph on the Cerro Tololo Inter-American Observatory (CTIO) 4 m telescope to map the nebular velocity field in the 30 Doradus giant H II region. The kinematics of 30 Dor are very complex. The outer regions are charaterized by a smooth velocity field, but its turbulent velocity, 30-40 km/s Full Width Half Maximum (FWHM), is considerably higher than those in most smaller H II regions. In the central 9 min core, multiple velocity components are observed at most positions. The velocity field is dominated by a large number of expanding structures, ranging in size from 1 to 100 pc and expansion velocities of 20-200 km/s, and often organized into large hierarchical networks. The integral of these complex expanding structures in 30 Dor produces a surprisingly simple profile with a broad Gaussian core and faint extended wings. Several fast-expanding shells, with diameters of 2-20 pc, expansion velocities of 100-300 km/s, and kinetic energies of 0.5-10 x 10(exp 50) ergs have been identified. The large fast-expanding shells and networks are coincident with extended X-ray sources and are probably associated with supernova remnants embedded in supershells produced by the combined effects of stellar winds and supernovae from OB associations. We have used the intensity-calibrated echelle spectra to determine the basic physical and dynamical properties of the kinematic features in 30 Dor. The expanding shells contain roughly half of the kinetic energy in the 30 Dor complex, and this energy is several times higher than the gravitational binding energy of the region. The energetic requirements of the gas are consistent with the observed stellar content of 30 Dor, if the gas is accelerated by a combination of stellar winds and supernovae. Extrapolating the current energy injection rate in the nebula over the lifetime of the OB complex suggest that 30 Dor and its vicinity will evolve into a supergiant shell as seen in the LMC and other nearby galaxies.