Environmental Impacts of Supermassive Black Holes

AST-0307502 Begelman，Mitchell C.并非所有受到黑洞影响的物质最终都会进入黑洞内部，因为只有少量的吸积释放出足够的能量来排出更大的量。 这些流出物携带大量能量，深刻地影响着黑洞的环境。最近的X射线和无线电观测表明，冷却流--被认为是冷却和坍缩到星团中心的气体--可以被流出的能量完全阻止。本项目将研究这种影响的细节，这种影响不是由爆发产生的，而是通过一种称为“对流加热”的温和过程产生的，星系团的X射线发射大气层，以及在高红移的超大质量黑洞的生长。 研究人员将通过分析建模和最先进的数值模拟来研究太阳能加热的物理基础及其影响。 他们将研究星系之间的紧耦合及其中心黑洞的形成是否是通过释放的能量反馈而产生的，并对超大质量黑洞的形成和演化与星系和星系团的形成和演化之间的联系有了新的认识。这项研究将促进本科科学教育，并有助于公众对科学研究的理解，因为黑洞具有广泛的魅力，这使它们成为一个极好的“钩子”。 PI还将保持与科学记者和流行杂志的联系，继续自己的写作，并将其研究成果用于他的一般课程。

AST-0307502Begelman, Mitchell C.Not all of the matter which comes under a black hole's influence ends up inside, because accretion of just a small amount releases enough energy to expel a much larger amount. These outflows carry a lot of energy and profoundly affect the black hole's environment, as demonstrated by recent X-ray and radio observations showing that cooling flows - gas thought to be cooling and slumping into the centers of clusters - can be stopped completely by the outpouring energy.This project will study the details of this influence, exerted not by outbursts but through a milder process called "effervescent heating", on the X-ray-emitting atmospheres of galaxy clusters, and on the growth of supermassive black holes at high redshift. The investigators will study the physical basis of effervescent heating and its implications through analytic modeling and state-of-the-art numerical simulations. They will research whether the tight coupling between galaxies and the formation of their central black holes arises from feedback via the released energy, and achieve new understanding of how the formation and evolution of super-massive black holes is linked to the formation and evolution of galaxies and galaxy clusters.The research will promote undergraduate science education and help with the general public's understanding of scientific research, because black holes have a widespread fascination which makes them an excellent "hook". The PI will also maintain his contacts with science journalists and popular magazines, continue with his own writings, and use his research results in his generally available courses.