论文标题
最大星系中的巴里昂周期
Baryon Cycles in the Biggest Galaxies
论文作者
论文摘要
宇宙最大的星系既有广阔的气氛，又具有超大质量的中央黑洞。本文回顾了一对大型星系夫妇的两个组成部分，并如何调节银河系的恒星形成率。超级质量黑洞与大规模气氛之间的相互作用模型表明，随着冷气云在黑洞上的积聚，释放的能量悬挂在一个状态下，该状态略有稳定，以形成冷云。越来越多的观察性证据表明，许多巨大的星系，从巨大的星系簇中央星系到我们自己的银河系，都接近那个边际状态。在如此边际状态下星系中恒星形成的气体供应与其恒星的中央速度分散（Sigma_v）紧密相关。因此，我们探讨了一个模型的后果，在黑洞积聚期间释放的能量在Sigma_v超过星系超新星加热速率确定的临界值时会关闭恒星形成。
The universe's biggest galaxies have both vast atmospheres and supermassive central black holes. This article reviews how those two components of a large galaxy couple and regulate the galaxy's star formation rate. Models of interactions between a supermassive black hole and the large-scale atmosphere suggest that the energy released as cold gas clouds accrete onto the black hole suspends the atmosphere in a state that is marginally stable to formation of cold clouds. A growing body of observational evidence indicates that many massive galaxies, ranging from the huge central galaxies of galaxy clusters down to our own Milky Way, are close to that marginal state. The gas supply for star formation within a galaxy in such a marginal state is closely tied to the central velocity dispersion (sigma_v) of its stars. We therefore explore the consequences of a model in which energy released during blackhole accretion shuts down star formation when sigma_v exceeds a critical value determined by the galaxy's supernova heating rate.
