Supershells and propagating star formation
Supershells and propagating star formation
复制标题
超级壳层和传播恒星的形成
DOI：
10.1086/165267
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发表时间：
1986
期刊：
影响因子：
--
通讯作者：
M. Kafatos
中科院分区：
文献类型：
--
作者：
R. McCray;M. Kafatos
来自OB协会的恒星风和反复出现的超新星将在星际介质中产生一个日冕气体空腔，半径大于100pC，周围环绕着一个致密的、不断膨胀的冷星际气体外壳。如果该协会具有典型的初始质量函数，它的超新星爆炸将以几乎恒定的速度向超级贝壳注入能量约50 Myr。当辐射冷却变得重要时，或者当贝壳破裂穿过星系的气盘时，超级壳牌失去了内部压力，进入了扫雪阶段，通常是在半径为100-300pC的10 Myr之后的几次。大约在同一时间，超级壳体变得引力不稳定，形成了巨大的分子云，这是新恒星形成的场所。从21厘米的发射线测量、光学发射线测量和对超新星残骸的研究中，有广泛的证据表明银河系和其他螺旋星系和不规则星系中存在超壳。超壳层的引力不稳定性为诱导恒星形成提供了物理机制，并可能解释恒星形成的爆发，特别是在不规则星系中。参考文献85篇。
Stellar winds and repeated supernovae from an OB association will create a cavity of coronal gas in the interstellar medium, with radius greater than 100 pc, surrounded by a dense, expanding shell of cool interstellar gas. If the association has a typical initial mass function, its supernovae explosions will inject energy into the supershell at a nearly constant rate for about 50 Myr. The supershell loses its interior pressure and enters the snowplow phase when radiative cooling becomes important or when the shell bursts through the gas disk of a galaxy, typically after a few times 10 Myr and with a radius of 100-300 pc. At approximately the same time, the supershell becomes gravitationally unstable, forming giant molecular clouds which are sites for new star formation. There is widespread evidence for supershells in the Galaxy and other spiral and irregular galaxies from 21-cm emission-line surveys, optical emission-line surveys, and studies of supernova remnants. The gravitational instability of the supershells provides a physical mechanism for induced star formation and may account for bursts of star formation, especially in irregular galaxies. 85 references.