Astrophysics at St Andrews: 2012-2014

圣安德鲁斯天文学小组对起源的问题很感兴趣：星系、恒星和行星从何而来？它们的形成有哪些基础物理学解释？我们在解决复杂的数学问题方面处于世界领先地位，我们使用新颖的方法，如高精度的观察和超级计算机的模拟。我们通过苏格兰大学物理联盟（SUPA）和国际上的其他团体加入了苏格兰的行列，寻找地球大小的热行星和冷行星，寻找可能存在生命的宜居世界。我们的研究跨越了广泛的尺度，从发现几光年外恒星周围的行星系统到测量作用于整个宇宙的引力。我们通过使用机器人广角摄像机来发现“热木星”，这些摄像机监测数千颗恒星，以发现那些在轨道行星从其母恒星前面经过时短暂变暗的恒星。我们发现了更冷、更小、更像地球的行星，利用机器人望远镜观察引力透镜，利用爱因斯坦的预言，即一颗行星穿过视线，漂向遥远的背景恒星，会使光线弯曲。我们正在通过观察尘埃颗粒和鹅卵石的辐射来了解行星是如何形成的，这些尘埃颗粒和鹅卵石要么是在形成行星的过程中，要么像我们的彗星一样，是行星形成过程的残留物。年轻的恒星有很强的磁场，与轨道行星和它们自己的磁场相互作用。我们正在研究这种相互作用的特征，这将有助于我们了解行星是如何形成和演化的。我们正在研究低温褐矮星和系外行星大气中的矿物云和闪电的物理学。这些过程改变了我们对行星系统的看法，并将帮助我们了解地球上火山爆发时的尘埃和闪电。我们正在使用观测和数值模拟来研究恒星是如何在星系中形成的，以及年轻恒星的反馈是如何驱动一种动态的、冒泡的星际介质的，即新恒星诞生的尘埃气体。我们包括大质量恒星死亡时的高能超新星爆炸，以及大质量恒星发出的电离辐射，这些辐射将星系中的气体加热到1万摄氏度以上。在宇宙尺度上，我们正在对35万个星系进行调查，研究它们的结构是如何形成的。我们将学习星系是如何形成它们特有的平盘、旋臂和中心凸起的形状的。这将帮助我们了解更多奇特的现象，比如星系的中心引擎，潜伏在星系中心区域的超大质量黑洞，目的是了解它们是如何成长的。我们正在研究引力如何在星系和宇宙的尺度上起作用。恒星在星系中的运行速度如此之快，以至于似乎没有足够的质量将星系聚集在一起。在更大的尺度上，宇宙本身的膨胀正在加速。这些谜题告诉我们，尽管我们在小尺度上了解重力，足以将太空探测器发射到其他行星上，但在更大尺度的星系和更远的地方，它可能会有所不同。我们正在研究暗物质和暗能量理论的替代方案，将我们的预测与观测结果进行比较，以测试引力是如何工作的。因此，我们解决了科学路线图中的关键问题：极端条件下的物理定律是什么？星系、恒星和行星是如何形成和演化的？我们在宇宙中是孤独的吗？我们的科学计划利用主要的国际和空间天文台，如ASKAP， eMERLIN，赫歇尔，开普勒，斯皮策，HST，未来的设施，包括ALMA， JWST， SKA和PLATO。

The St Andrews astronomy group is interested in questions of origins: where do galaxies, stars and planets come from, and what fundamental physics explains their formation? We are world leaders in solving intricate mathematical problems, and we use novel methods such as observations at very high precision and simulations with super-computers. We are joined by other groups across Scotland via the Scottish Universities Physics Alliance (SUPA), and internationally, in searching for hot and cool Earth-sized planets, homing in on habitable worlds where life could exist.Our research spans a wide range of size scales, from discovering planetary systems around stars a few light years away to measuring the force of gravity acting on the whole universe. We discover `hot Jupiters' by using robotic wide-angle cameras that monitor thousands of stars to find those that briefly dim each time an orbiting planet passes in front of its parent star. We discover cooler and smaller more Earth-like planets, using robotic telescopes to watch gravitational lenses, exploiting Einstein's prediction that a planet drifting across the sightline to a distant background star bends its light. We are learning about how planets form by looking at the radiation from dust grains and pebbles, which are either in the process of forming planets or, like our comets, remnants of the planet forming process.Young stars have strong magnetic fields that interact with orbiting planets and their own magnetic fields. We are studying the signatures of this interaction, which will help us to understand how planets form and evolve. We are investigating the physics of mineral clouds and lightning in atmospheres of cool brown dwarf stars and extrasolar planets. These processes alter our view of planetary systems and will help us understand dust and lightning in volcanic eruptions on Earth. We are using observations and numerical simulations to study how stars form in galaxies and how feedback from young stars drives a dynamic, bubbling interstellar medium, the dusty gas from which new stars are born. We include energetic supernova explosions when massive stars die and the ionising radiation from massive stars that heats the gas in the galaxy to temperatures above than 10,000 degrees Centigrade.On cosmological scales, we are conducting a survey of 350,000 galaxies to study how their structure emerges. We will learn how galaxies form into their characteristic shapes of flat discs, spiral arms and central bulges. This will help us to understand more exotic phenomena such as the central engines of galaxies, the supermassive black holes that lurk in their central regions, with the aim of understanding how they grow. We are studying how gravity works on the scale of galaxies and the universe. Stars orbit in galaxies so fast that there does not appear to be enough mass to hold the galaxies together. On larger scales, the expansion of the universe itself is accelerating. These puzzles tell us that although we understand gravity on small scales, well enough to send space probes to other planets, it may be different on the larger scales of galaxies and beyond. We are studying alternatives to current ideas of Dark Matter and Dark Energy, comparing our predictions with observations to test how gravity works. Thus we address key questions in the Science Roadmap: What are the laws of physics in extreme conditions? How do galaxies, stars and planets form and evolve? Are we alone in the Universe? Our science programme exploits major international and space observatories such as ASKAP, eMERLIN, Herschel, Kepler, Spitzer, HST, future facilities including ALMA, JWST, SKA, and PLATO.