High Energy Astrophysics at Southampton

在恒星尺度上，我们感兴趣的是不同环境对高质量X射线双星(HMXB)群体演化的意义，特别是在银河系和SMC之间，不同的恒星形成率和金属丰度可能是至关重要的。在我们所看到的东西中，局域和星际遮蔽的相对重要性是什么？在这里，即将到来的SMC的2毫秒积分关键程序观测，几乎不受遮挡的影响，将具有很大的价值。球状星团是研究恒星动力学和恒星演化的优秀实验室，特别是在了解最奇异的恒星群方面。我们正在收集对球状星团的大样本的观测，以了解哪些星团属性对这些奇异恒星的产生最重要，并将其与低恒星密度矮球星系进行比较，以将恒星演化与恒星动力学分开。总部设在荷兰的低频无线电阵列LOFAR即将打开一扇新的宇宙之窗，提供第一个无线电“全天监测器”。我们将研究相干射电爆发，可能与合并的中子星有关，在极远的距离(z=7)可探测到，提供了星系间介质的独特探测器，甚至可能通过识别LIGO激发事件测试引力和宇宙距离尺度理论。我们将继续研究X射线双星中吸积和流出(喷流)之间的耦合，以及它如何与活动星系核(建立了与黑洞质量的标度定律)、吸积中子星和白矮星的平行过程有关。我们已经积累了第一个全面的黑洞光谱状态数据库，并将扩展这一分析，以包括X射线计时和射电结果。因此，我们将对黑洞吸积流与相对论喷流的形成和能量之间的关系进行迄今为止最全面的分析。该结果可应用于星系和星系团的活动星系核反馈。我们将极大地提高我们对塞弗特星系和银河系双星中特征X射线时间尺度、质量和吸积率之间的标度关系的认识，从而检验这一重要宇宙关系的物理模型。我们将确定这种关系是否适用于喷气主导的“blazars”，这意味着变异性的普遍起源。我们正在建立一个基于传播波动的模型，以提供对所有光谱-时间关系的物理理解，以得出物理参数，例如光盘发射率分布。这个模型，加上额外的X射线再处理，也应该解释活动星系核中的X射线/光学关联，所以我们将用我们的X射线/光学监测来测试它。为了提供对附近宇宙的普查，以建立更遥远的宇宙模型，我们大量参与了对附近星系样本的eMerlin遗留调查。现在人们普遍认为，一些过程必须重新加热星系团中的气体，否则将在星系团的核心中发现大量看不到的冷气体。但是加热机制是什么呢？在我们最具理论意义的项目中，我们将通过MHD模拟，研究合并事件、星系运动和活动星系核外流驱动的湍流能量耗散是否可能起到作用。在最大的尺度上，活动星系核和恒星形成星系(SFG)都对微弱的射电源群体做出了贡献，但混合在一起的是什么呢？通过结合无线电形态和各种频谱能量诊断，我们可以区分AGN和SFG。因此，使用射电光度作为恒星形成率(SFR)的指示器，我们可以以一种与吸收无关的方式确定宇宙SFR的演化。我们将把这项技术推向更高的红移，作为eMerlin深场遗产调查的主要贡献者，并探索SFGs和AGN之间的关系。

On the stellar scale we are interested in the significance of different environments on the evolution of high mass X-ray binary (HMXB) populations, in particular between the Milky Way and the SMC, where differing star formation rates and metallicities could be crucial. What are the relative importances of local and interstellar obscuration in what we see? Here the upcoming 2Msec INTEGRAL Key Programme observation of the SMC, almost unaffected by obscuration, will be of great value. Globular clusters are outstanding laboratories for studying stellar dynamics and stellar evolution, especially for understanding the most exotic stellar populations. We are drawing together observations of large samples of globular clusters to understand which cluster properties are most important for the production of these exotic stars, and comparing with low stellar density dwarf spheroidal galaxies to isolate the stellar evolution from stellar dynamics. The Netherlands-based low frequency radio array, LOFAR, is about to open a new window on the universe providing the first radio `all sky monitor'. We will study coherent radio bursts, perhaps associated with merging neutron stars, detectable at enormous distances (to z=7), providing a unique probe of the intergalactic medium and possibly even testing theories of gravity and cosmological distance scales via identification of LIGO inspiral events We will continue our research into the coupling between accretion and outflow (jets) in X-ray binaries, and how it relates to parallel processes in AGN (where scaling laws with black hole mass are established), accreting neutron stars and white dwarfs. We have amassed the first comprehensive database of black hole spectral states and will extend this analysis to include X-ray timing and radio results. Thus we will produce the most comprehensive analysis to date of the relation between black hole accretion flows and the formation and power of relativistic jets. The results can be applied to AGN feedback in galaxies and clusters. We will greatly improve our knowledge of the scaling relationship between characteristic X-ray timescale, mass and accretion rate in Seyfert galaxies and Galactic binaries, thus testing physical models for this important universal relationship. We will determine whether the relationship applies in jet dominated ``blazars'', implying a universal origin for variability. We are building a model, based on propagating fluctuations, to provide physical understanding of all spectral-timing relationships to derive physical parameters, eg disc emissivity profile. This model, with additional X-ray reprocessing, should also explain X-ray/optical correlations in AGN so we will test it against our X-ray/optical monitoring. To provide a census of the nearby universe on which models of the more distant universe can be built, we are heavily involved in eMERLIN legacy surveys of nearby galaxy samples It is now widely accepted that some process must reheat the gas in galaxy clusters or large amounts of cool gas, which are not seen, would be found in the cores of clusters of galaxies. But what is the heating mechanism? In our most theoretical project we will investigate, via MHD simulations, whether the dissipation of turbulent energy, driven by merger events, galaxy motions and AGN outflows, may be responsible. On the largest scales, both AGN and starforming galaxies (SFGs) contribute to the faint radio source population, but what is the mix? By combining radio morphology with a variety of spectral energy diagnostics we can distinguish AGN from SFGs. Hence, using radio luminosity as a starformation rate (SFR) indicator, we can determine the evolution of the cosmic SFR in an absorption-independent manner. We will push this technique to much higher redshifts, as major contributors to eMERLIN deep field legacy surveys, and also probe the relationship between SFGs and AGN.