Cold, clumpy accretion onto an active supermassive black hole
Cold, clumpy accretion onto an active supermassive black hole
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活跃的超大质量黑洞上的冷块状吸积物
作者：
Grant R. Tremblay;Grant R. Tremblay;J. Oonk;J. Oonk;F. Combes;P. Salomé;C. O’Dea;C. O’Dea;S. Baum;S. Baum;G. Voit;M. Donahue;B. McNamara;Timothy A. Davis;Timothy A. Davis;Michael McDonald;A. Edge;T. Clarke;Roberto Galván;Roberto Galván;M. Bremer;Louise O. V. Edwards;A. C. Fabian;S. Hamer;Yuan Li;A. Maury;H. Russell;A. Quillen;C. Urry;J. S. Sanders;M. Wise
所谓的吸积流为星系中心的超大质量黑洞的增长提供动力，被认为是由非常热的等离子体的平滑，稳定的流动所主导，但现在的观测结果显示，非常冷的分子云在附近的巨型椭圆星系的核中的超大质量黑洞上聚集吸积。所谓的吸积流为星系中心的超大质量黑洞的生长提供动力，通常被认为是由非常热的等离子体的平滑，稳定的流动所主导，但几乎没有直接的证据支持这一观点。对阿贝尔2597星系团的新观测为另一种模型提供了证据，即黑洞的冷吸积，最近通过模拟和理论预测，但没有直接观察到。这些数据揭示了寒冷的，clusified分子云落向附近一个巨大椭圆星系核中的一个活跃的超大质量黑洞。星系中心的超大质量黑洞可以通过气体的吸积而增长，释放出的能量可能会在星系范围内调节星星的形成1，2，3。然而，为黑洞生长提供动力的气体燃料库的性质在很大程度上不受观测的约束，而是通常被简化为非常热的气体的平滑球形流入。最近的理论5，6，7和simulations 8，9，10，而不是预测，吸积可以占主导地位的随机，cluberous分布的非常冷的分子云-偏离“热模式”吸积模型-虽然明确的观测支持这一预测仍然难以捉摸。在这里，我们报告的意见，揭示了一个寒冷的，clusional吸积流的超大质量黑洞燃料水库的核心的阿贝尔2597布里渊星系团星系（BCG），附近（红移z = 0.0821）巨大的椭圆星系包围的致密晕的热等离子体11，12，13。在适当的条件下，热不稳定性会产生一场冷云雨，落向星系中心，在星系核心发现的千秒差距大小的分子星云中维持星星的形成。观测结果表明，这些冷云也会加速黑洞的吸积，揭示出分子云以每秒约300公里的速度向内移动时所投下的“阴影”，这些分子云将作为明亮的背光。先前在极高的空间分辨率下观测到的较温暖的原子气体的确凿证据，沿着基于几何和概率的简单论点，表明这些云在黑洞最里面的一百秒差距内，并且更接近它。
The so-called accretion flow that powers the growth of supermassive black holes in galaxy centres is assumed to be dominated by a smooth, steady flow of very hot plasma, but now observations instead reveal a clumpy accretion of very cold molecular clouds onto a supermassive black hole in the nucleus of a nearby giant elliptical galaxy. The so-called accretion flow that powers the growth of supermassive black holes in galaxy centres is often assumed to be dominated by a smooth, steady flow of very hot plasma, but there is little direct evidence to support this idea. New observations of the Abell 2597 galaxy cluster provide evidence for an alternative model, cold accretion onto black holes, recently predicted by simulations and theory, but not directly observed. The data reveal cold, clumpy molecular clouds falling towards an active supermassive black hole in the nucleus of a nearby giant elliptical galaxy. Supermassive black holes in galaxy centres can grow by the accretion of gas, liberating energy that might regulate star formation on galaxy-wide scales1,2,3. The nature of the gaseous fuel reservoirs that power black hole growth is nevertheless largely unconstrained by observations, and is instead routinely simplified as a smooth, spherical inflow of very hot gas4. Recent theory5,6,7 and simulations8,9,10 instead predict that accretion can be dominated by a stochastic, clumpy distribution of very cold molecular clouds—a departure from the ‘hot mode’ accretion model—although unambiguous observational support for this prediction remains elusive. Here we report observations that reveal a cold, clumpy accretion flow towards a supermassive black hole fuel reservoir in the nucleus of the Abell 2597 Brightest Cluster Galaxy (BCG), a nearby (redshift z = 0.0821) giant elliptical galaxy surrounded by a dense halo of hot plasma11,12,13. Under the right conditions, thermal instabilities produce a rain of cold clouds that fall towards the galaxy’s centre14, sustaining star formation amid a kiloparsec-scale molecular nebula that is found at its core15. The observations show that these cold clouds also fuel black hole accretion, revealing ‘shadows’ cast by the molecular clouds as they move inward at about 300 kilometres per second towards the active supermassive black hole, which serves as a bright backlight. Corroborating evidence from prior observations16 of warmer atomic gas at extremely high spatial resolution17, along with simple arguments based on geometry and probability, indicate that these clouds are within the innermost hundred parsecs of the black hole, and falling closer towards it.