Warwick Astronomy and Astrophysics Rolling Grant 2008-2013

在这项研究计划中，我们将绘制最终导致宇宙中最剧烈事件，超新星和伽马射线爆发的复杂路径，并研究恒星对其行星系统的影响。虽然我们在天空中看到的星星似乎永远不会改变，但实际上宇宙是不断发展的。在某些情况下，我们可以亲眼看到这种情况发生，最引人注目的是天文学家称为超新星和伽马射线爆发的巨大爆炸，在此期间，整个恒星在几秒钟内被撕裂。许多这样的事件只能起源于被称为双星的紧密的恒星对。物理学最近最引人注目的发现之一，被认为是驱动宇宙膨胀速度加速的“暗能量”，正是基于对这些物体的观察。只有当我们理解了驱动双星演化的过程，才能对这类恒星的数量和性质有全面的了解。我们将执行一项方案，对通过大面积天空调查发现的物体进行观测和分析。我们观察的许多系统都被预测为“引力辐射”的良好发射器，这些辐射是空间结构中以光速传播的微小涟漪，可能在未来15年内直接在地球上被检测到，这让我们直接了解引力的本质。我们计划的工作将有助于确定引力波潜在双星发射体的数量和性质。最极端的系统，伽马射线暴，是年轻宇宙的探测器，因为它们非常明亮，可以在宇宙的任何地方看到。然而，它们也很罕见，因此无法在附近看到，使它们的起源神秘。我们将进行双重研究，以确定伽马射线爆发的祖先恒星的性质，并探索导致年轻宇宙中第一批恒星形成的条件。在过去的十年里，在太阳系外发现了大约200个行星系统。这项工作的一个大惊喜是发现了类似于行星的行星，它们的轨道非常接近它们的宿主恒星。有些是如此接近，他们甚至可能蒸发。在这个项目中，我们将研究宿主恒星对其行星的影响，那里的条件在许多方面与近距离双星相似。我们还将研究最近在被称为白色矮星的古老致密恒星周围发现的行星物质盘的性质和起源。白色矮星是大多数恒星的最终状态，我们的目标是了解行星系统如何以及以何种形式在其宿主恒星的生命周期中生存下来。

In this research programme we will map the complex pathways that culminate in the most violent events in the Universe, supernovae and gamma-ray bursts, and study the effects that stars have on their planetary systems. Although the stars we see in the sky never seem to change, in reality the Universe is constantly evolving. In some cases we can see this happening before our very eyes, most dramatically in the huge explosions astronomers know as supernovae and gamma-ray bursts during which entire stars are torn apart within seconds. Many of these events can only originate within tight pairs of stars known as binary stars. One of the most remarkable recent discoveries of physics, the 'dark energy' which is thought to be driving the expansion rate of the Universe to accelerate, is based upon the observation of precisely such objects. A full understanding of the numbers and properties of such stars can only come if we understand the processes which drive binary evolution. We will carry out a programme of observation and analysis of objects found through large area surveys of the sky. Many of the systems that we look at are predicted to be good emitters of 'gravitational radiation', tiny ripples in the fabric of space that travel at the speed of light and may be detected directly at Earth within the next 15 years, giving us a direct insight into the nature of gravity. The work we plan will help to establish the numbers and properties of the potential binary emitters of gravitational waves. The most extreme systems of all, the gamma-ray bursts, are probes of the young Universe as they are so bright that they can be seen anywhere in the Universe. However they are also rare, and so cannot be seen close at hand, leaving their origins mysterious. We will carry out a dual study to determine the nature of the progenitor stars of gamma-ray bursts and to probe the conditions that lead to the formation of the first stars in the young Universe. Over the past decade some 200 planetary systems have been discovered outside our solar system. A big surprise of this work was the discovery of Jupiter-like planets orbiting very close to their host stars. Some are so close that they may even evaporate. In this programme we will study the effect of the host stars upon their planets, where conditions are in many ways similar to those of close binary stars. We will also study the nature and origin of disks of planetary material that have recently been detected around the old dense stars known as white dwarfs. White dwarfs are the final state of most stars, and our aim is to understand how, and in what form, planetary systems can survive the life-cycle of their host stars.