论文标题
隆升刺激的热不稳定冷却：扰流板簇
Thermally Unstable Cooling Stimulated by Uplift: The Spoiler Clusters
论文作者
论文摘要
我们分析了五个星系簇的Chandra X射线观测值，它们的大气冷却时间，熵参数和中央星系中的自由下落时间比率分别低于1 Gyr，低于30 kev cm^2，分别在20 <tcool/tfff <50之间。这些热力学特性通常与中央星系中的分子云，明亮的H-α发射和恒星形成有关。但是，这些簇中没有一个在接受数据库中指示的H-α，也没有明显的恒星形成速率或可检测到的分子气体。其中，仅RBS0533具有可检测到的无线电/X射线气泡，在冷却气氛中通常观察到。不存在抬高，高金属性大气气体的签名。尽管它具有突出的X射线气泡，但RBS0533缺乏显着水平的分子气体。在这些系统中，冷气不存在，这可能是因为它们的无线电来源未能将低熵大气气体提升至高度，在这种情况下，冷却时间与自由下落时间的比率低于统一。
We analyzed Chandra X-ray observations of five galaxy clusters whose atmospheric cooling times, entropy parameters, and cooling time to free-fall time ratios within the central galaxies lie below 1 Gyr, below 30 keV cm^2, and between 20 < tcool/tff < 50, respectively. These thermodynamic properties are commonly associated with molecular clouds, bright H-alpha emission, and star formation in central galaxies. However, none of these clusters have detectable H-alpha indicated in the ACCEPT database, nor do they have significant star formation rates or detectable molecular gas. Among these, only RBS0533 has a detectable radio/X-ray bubble which are commonly observed in cooling atmospheres. Signatures of uplifted, high metallicity atmospheric gas are absent. Despite its prominent X-ray bubble, RBS0533 lacks significant levels of molecular gas. Cold gas is absent at appreciable levels in these systems perhaps because their radio sources have failed to lift low entropy atmospheric gas to an altitude where the ratio of the cooling time to the free-fall time falls below unity.
