PATT Linked Grant Support for the Bristol Astrophysics Group

布里斯托尔天体物理学小组致力于一些项目，这些项目需要使用世界上最大的望远镜进行仔细的观测。这项提议要求提供两年的经费，用于支付前往这些望远镜的旅费和在这些望远镜工作期间的生活费。在对微波背景辐射的研究中，消除前景辐射源的污染是很重要的，因为前景辐射源会混淆我们对背景本身的测量。这是利用美国和其他地方的射电望远镜的一系列观测来完成的。许多测量结果与星系团投射在微波背景上的“阴影”有关。对这些星系团进行广泛的无线电和光学研究，以了解它们的质量并深入了解它们是如何形成的，也是我们工作的重要部分。我们对活跃星系的研究主要是使用轨道X射线望远镜完成的，这些星系在其核心拥有非常大质量的黑洞，但为了了解发射的物理，也必须看到射电、红外线和光学波段的发射。在这一点上，小组成员再次在世界范围内广泛使用望远镜，从澳大利亚的无线电干涉仪到智利的光学望远镜。这些活跃星系的小规模模型可以在我们自己的银河系中找到，在质量是太阳质量几倍的黑洞系统中。研究这些系统的方法与研究活动星系的方法相同，但还需要跟踪黑洞附近物质发射亮度的快速变化，这些变化告诉我们物质流入和相关的高速流抛射的物理原理。我们银河系外工作的一个统一线索是关于宇宙中的结构是如何形成和随时间变化的。因此，我们的观测有很大一部分是致力于寻找和描述最早的星系和星系团，然后看看最远的星系和星系团与那些离我们更近的星系和星系团有什么不同，因此在宇宙生命的后期才能看到，所以更古老。在这项工作中必须使用从无线电到光学的各种地面望远镜，其中大部分工作使用智利欧洲南方天文台的望远镜。与更远的星系相比，我们可以更详细地研究附近的星系，我们还可以观察附近的星系群--特别是那些质量最低的星系，它们在数量上主导着星系的数量，它们的性质可能与它们质量更大的近亲完全不同。最后，我们还研究了我们自己的银河系，观察了被超新星或年轻恒星加热的恒星之间的气体，以及发射相干(脉泽)辐射的致密气体块。

The Bristol Astrophysics Group works on a number of programmes that require careful observations to be made with the world's largest telescopes. This proposal requests two years of funding for travel to those telescopes and subsistence while working at them. In studies on the microwave background radiation, the left-over radiation from the Big Bang, it is important to remove contamination from foreground sources of emission that confuse our measurements of the background itself. This is done using a series of observations at radio-telescopes in the USA and elsewhere. Many of the measurements relate to the 'shadows' cast on the microwave background by clusters of galaxies. Extensive radio and optical studies of those clusters, to understand their masses and to gain insights into how they formed, are also a significant part of our work. Our work on active galaxies, which host very massive black holes in their nuclei, is principally done using orbiting X-ray telescopes, but to understand the physics of the emission it is essential to see also the emission in the radio, infra-red, and optical bands. Here again Group members make extensive use of telescopes world-wide, from the radio interferometers in Australia to optical telescopes in Chile. Small-scale models of these active galaxies can be found in our own Galaxy, in black hole systems with masses a few times the mass of the Sun. Work on these systems is done in the same way as for the active galaxies, with the extra requirement to follow rapid changes in the brightness of emission from matter near the black holes that tell us about the physics of the infall of matter and the associated ejection of high-speed flows. A unifying thread of our extragalactic work is on how structure in the Universe forms and changes over time. A large fraction of our observing is therefore dedicated to finding and characterizing the earliest galaxies and clusters, and then seeing how the most distant galaxies and clusters differ from those closer to us, which are therefore seen later in the life of the Universe, and so are older. A wide range of ground-based telescopes has to be used in this work, from the radio to the optical, with much of the work using the telescopes of the European Southern Observatory in Chile. Nearby galaxies can be studied in more detail than the more distant ones, and we also look at the populations of galaxies nearby - especially those of the lowest mass, which dominate the galaxy population by number, and have properties that can be quite different from their more massive cousins. Finally, we also work on our own Galaxy, looking at the gas between the stars, which has been heated by supernovae or young stars, and at the dense lumps of gas that emit coherent (maser) radiation.