EXTREME PHYSICS AROUND BLACK HOLES: UNDERSTANDING ACCRETION-DISK PHYSICS AT THE EDGE OF THE BLACK-HOLE EVENT HORIZON

银河系中的黑洞质量在太阳的5到15倍之间，是由一颗大质量恒星在超新星爆炸中形成的。黑洞是如此巨大，被限制在如此小的空间中，以至于连光都无法逃脱它的引力。幸运的是，一些黑洞是在双星系统中，有一颗与太阳相似或比太阳小的恒星。如果黑洞和伴星距离足够近，黑洞产生的强大引力将慢慢“吸走”伴星的气体，使其变形为梨形恒星。被黑洞吸走的气体不会直接落入黑洞，而是像洗澡水一样绕着一个塞孔旋转，形成一个气体盘，天文学家称之为吸积盘。吸积盘的基本物理原理是什么？产生超高速风和喷气需要什么物理成分？这位博士生将加入高能天体物理学小组，以解决吸积盘物理学的一些最基本的问题。为了做到这一点，学生将使用NASA最新的x射线仪器“中子星内部成分探测器”的高时间分辨率数据，结合最先进的光学、红外和无线电设备的数据。

Black holes in our Galaxy have masses between 5 and 15 times that of our Sun, and are formed when a massive star explodes in a Supernova. A black hole is so massive and confined in such a small volume in space, that not even light can escape its gravitational attraction. Fortunately, some black holes are in binary systems with a star similar to, or smaller than our Sun. If the black hole and the companion star are close enough, the strong gravity produced by the black hole will slowly "suck" gas from its companion, deforming it into a pear-shape star. The gas pulled off by the black hole does not fall directly into it, but swirls in like bath water around a plug-hole, forming a disk of gas which astronomers call accretion disk.What are the fundamental physics that rule accretion disks? What are the physical ingredients needed to produce ultra-fast winds and jets? The PhD student will join the group of high-energy astrophysics in order to tackle some of the most fundamental questions of accretion disk physics. To do so, the student will use high-time resolution data from NASA's newest X-ray instrument "Neutron star Interior Composition Explorer", in combination with data from state-of-the-art optical, infrared and Radio facilities.