UCL Astrophysics Consolidated Grant 2018-2021

我们现在知道，我们的宇宙不仅在膨胀，而且在以不断增长的速度膨胀。在一种名为暗能量的神秘驱动力的推动下，星系，如我们的银河系，正以如此巨大的加速度相互冲离，以至于即使是强大的引力也无法将宇宙保持在一起。伦敦大学学院天体物理学小组的研究人员正在用一项雄心勃勃的未来几年研究计划来检验这些发现，该计划旨在通过查看全面的天空地图来了解我们宇宙的组成和演化。但包含数十亿个星系和其他更奇异的天体(如类星体)的详细星表只是个开始--在伦敦大学学院，我们正在领导将这些星表转化为物理洞察的努力。在接下来的几年里，我们将专注于将我们调查的原始数据转化为对早期宇宙的基本物理的理解；神秘的中微子粒子的质量；“暗物质”和“暗能量”的性质和分布；以及宇宙在第一批恒星和类星体形成时发光的方式。为了了解星系是如何形成的，我们将探索恒星是如何从巨大的气体和尘埃云中形成的，以及恒星之间发生的化学作用如何影响和控制这些关键的过程。我们将学习在恒星形成的最早阶段，气体云和尘埃云如何以不同的方式收缩，以及如何使用对复杂分子的观察来研究相关的物理过程。我们还将分析新形成的大质量原恒星的示踪物，包括相关的喷流和流出。我们不仅将研究我们银河系中的分子和尘埃，还将研究邻近星系以及位于宇宙边缘的遥远、非常年轻的星系中的分子和尘埃。通过机械、化学和辐射反馈，大质量恒星(出生时质量大于20个太阳质量)的影响远远超出了它们所处环境的范围，在更广泛的银河系生态中发挥着至关重要的作用。为了了解这种影响，我们建议在大量射电和毫米观测的基础上进行研究，以调查大质量恒星演化的关键驱动因素，包括通过强风和双星系统中的相互作用造成的质量损失。最近对系外行星的发现表明，几乎每一颗恒星都有一个行星系统，地球只是我们银河系数十亿颗行星中的一颗。在探测到的3500多颗系外行星中，约有40个已知的超级地球。所有这些岩石行星的轨道都很短，因此大气层很热。其中一些行星非常像我们的地球，但非常年轻的地球可能有融化的岩石和蒸汽水大气层。人们对这些熔岩世界知之甚少。它们是什么做的？它们会冷却到可以维持生命的温度吗？近年来，伦敦大学学院的团队开创了一项技术，可以从经过恒星前方时透过其大气层的恒星光中提取有关系外行星的信息，这导致了几项突破性的发现。为了开展对天空的研究，伦敦大学学院的仪器制造商正致力于提高更大、更复杂的地面望远镜设计和组装的精度，同时为未来的太空红外望远镜创造更轻、更低成本的结构，用于传输更高质量的数据。但除非我们的同胞分享我们团队工作的奇迹和兴奋，否则所有这些都将被浪费。我们将确保我们的团队成员继续通过演讲、公共活动和媒体解释他们的工作，激励下一代科学家，帮助和挑战行业开发新技术。

We now know that not only is our Universe expanding, but that it is expanding at an ever-increasing rate. Fuelled by a mysterious driver called Dark Energy, galaxies, such as our Milky Way are rushing away from each other at such enormous acceleration that not even the powerful force of gravity can hold the universe together. Researchers in UCL's Astrophysics Group are testing these discoveries with an ambitious programme of research for the coming years which aims to understand the makeup and evolution of our Universe by looking at comprehensive maps of the sky. But detailed catalogues containing billions of galaxies and other, more exotic objects such as quasars are just the start - at UCL we are leading efforts to turn these catalogues into physical insight. Over the coming years we will be focussing on turning raw data from our surveys into an understanding of, for example, the fundamental physics of the early Universe; the mass of the enigmatic neutrino particle; the nature and distribution of "dark matter" and "dark energy"; and the way in which the cosmos lit up as its first stars and quasars formed. In order to understand how galaxies are made of we will probe how stars form from vast gas and dust clouds and how the chemistry that goes on between the stars affects and controls these crucial processes. We will learn how clouds of gas and dust contract in different ways during the earliest stages of star-formation, and how observations of complex molecules can be used to study the physical processes that are involved. We will also analyse the tracers of newly forming high mass protostars, including the associated jets and outflows. We will not only study molecules and dust in our own Galaxy but also in nearby galaxies, and in distant, very young, galaxies located at the edge of the Universe. Through mechanical, chemical and radiative feedback the influence of massive stars (born with masses greater than 20 solar masses) extends well beyond the confines of their immediate environments, to play a vital role in the wider galactic ecology. To understand this influence we propose to conduct research based on substantial radio and millimetre observational surveys to investigate the key drivers of the evolution of massive stars, including mass-loss via powerful winds and interactions in binary systems. Recent discoveries of exoplanets indicate that almost every star has a planetary system, with Earth just one of several billion planets in our Galaxy. With more than 3,500 exoplanets detected, there are about 40 known super-Earths. All these rocky planets have very short orbits and hence hot atmospheres. Some of these planets are very like our own but very young Earths can have melting rock and steamed-water atmospheres. There is little knowledge about these lava-worlds. What are they made of? Are they ever going to cool down to the temperatures which could sustain life? In recent years, the UCL team has pioneered techniques to extract information about exoplanets from starlight filtered through their atmospheres as they pass in front of their star, which lead to several ground breaking discoveries. To carry out their studies of the heavens UCL's instrument makers are aiming to improve the precision with which larger and more sophisticated ground-based telescopes are designed and assembled and at the same time create lighter and lower cost structures for future infrared telescopes in space that can be used to deliver data of better quality.But all of this will be wasted unless our fellow citizens get to share in the wonder and excitement of our group's work. We will ensure that our team members continue to explain their work through talks and lectures, public events, and the media, inspiring the next generation of scientists, and helping and challenging industry to develop new technologies.