High Energy Astrophysics at Southampton

在最小的尺度上，我们感兴趣的是为什么脉冲星似乎倾向于SMC中低中性氢的环境。我们还对球状星团高密度环境中恒星碰撞和近距离撞击的产物感兴趣，并对银河系中致密物体（即黑洞、中子星或白矮星）的研究感兴趣，这些物体是氢原子发出光学光的强发射器。一些星系x射线双星源，由与太阳质量相似的黑洞和一颗更正常的恒星组成，以及吸积盘，物质通过吸积盘螺旋进入黑洞，有强烈的喷流。我们想了解喷流和热x射线发射日冕之间的关系，并找出喷流是如何从日冕中出现的。在某些情况下，内盘的消失伴随着物质沿喷流的喷射，我们将确定这种行为是否在活动星系中是典型的，即星系的发射是动力物质落在一个大质量黑洞上（即被吸积）。在20-100 keV波段，冷气体对光子的吸收不重要，因此我们获得了一个非常清晰的视野，我们正在用INTEGRAL测量银道面，以确定紧凑物体的无偏普查。随着时间的推移，我们将把这项调查扩展到河外的天空。我们研究活动星系的x射线变异性，以确定它们与星系x射线双星源的关系，以及特征时间尺度是否仅反映质量或其他参数，如吸积率。我们对附近星系的双星群和所谓的“超亮x射线源（ULXs）”感兴趣。ulx可能是长期寻找的黑洞，其质量介于星系双星和活动星系之间，因此对于测试基于质量的缩放关系非常重要。我们感兴趣的是双星和活动星系中不同波段（伽马射线、x射线、光学/红外、无线电）的发射是如何相关的，以及它们对质量的依赖是什么。我们感兴趣的是活动星系的喷流是如何加热星系团的。在最大的尺度上，我们感兴趣的是我们在无线电，x射线和红外波段中看到的不同微弱源群是否只是同一潜在现象的不同表现，以及大质量黑洞的增长可能与黑洞所在星系的增长有何关系。我们也在用计算机建立详细的理论模型，来解释我们在天空中看到的高能量的复杂变化。

On the smallest scales we are interested in why pulsars seem to favour the low neutral hydrogen environments in the SMC. We are also interested in the products of stellar collisions and near misses in the high density environment of globular clusters, and in studying the compact objects (ie black holes, neutron stars, or white dwarfs) in our Galaxy which are strong emitter of optical light from hydgrogen atoms. Some galactic X-ray binary sources, which consist of black hole of similar mass to our sun together with a more normal star have, as well as accretion discs, through which matter spirals onto the black hole, strong jets. We want to understand the relationship between the emission from jets and from the hot X-ray emitting coronae and to find out how the jet might emerge from the corona. In some cases the disappearance of the inner disc is followed by ejection of material along the jet and we shall determine whether such behaviour is typical in Active Galaxies, ie galaxies whose emission is powered material falling onto (ie being accreted) by a massive black hole. In the 20-100 keV band where absorption of photons by cold gas is unimportant, and so we obtain a very clear view, we are surveying the Galactic Plane with INTEGRAL to determine an unbiased census of compact objects. As time goes on, we will extend that survey to the extragalactic sky. We study the X-ray variability of Active Galaxies to determine how they relate to galactic X-ray binaries sources and whether characteristic timescales reflect only mass or another parameter such as accretion rate. We are interested in the binary populations of nearby galaxies and in the so-called `ultra luminous X-ray sources (ULXs)'. ULXs may be the long sought after black holes with masses intermediate between those of galactic binaries and Active Galaxies and so are very important for testing mass-based scaling relationships. We are interested in how the emission in different wavebands (Gamma-ray, X-ray, optical/IR, radio) in binaries and Active Galaxies is related and what is the dependence on mass. We are interested how the jet emission from Active Galaxies heats clusters of galaxies. On the largest scales, we are interested in whether the different faint source populations which we see in the radio, X-ray and IR bands are just different manifestations of the same underlying phenomenon and how massive black hole growth might be related to growth of the galaxy in which the black hole lives. We are also building detailed theoretical models, using computers, to explain the complicated variability which we see in the sky at high energies.