Exploring the early evolution of galaxies

探索星系的早期演化

基本信息

批准号：
ST/I001743/1
负责人：
Malcolm Bremer
金额：
$ 48.94万
依托单位：
University of Bristol
依托单位国家：
英国
项目类别：
Research Grant
财政年份：
2011
资助国家：
英国
起止时间：
2011 至无数据
项目状态：
已结题

来源：
https://gtr.ukri.org/projects?ref=ST%2FI001743%2F1
关键词：
Exploring early evolution galaxies

项目摘要

Central to our understanding of the the Universe is the topic of galaxy evolution. The details of how these large systems of stars, gas, dust and dark matter formed and evolved from the near-uniform matter distribution created by the Big Bang impact on how the properties of the rest of the Universe evolved. While there are quite detailed theoretical ideas about how galaxies form which feed in to multiple different and often competing/contradicting models of galaxy formation, observational measurements of early galaxies that can be used to constrain and test these models are currently rare. Particularly important to testing these models are observations of galaxies seen when the Universe was young. The galaxies seen should be the comparatively primitive building blocks of the much more mature and bigger galaxies seen today. Given the limited time available for such systems to evolve, their evolution should not be particularly complex and consequently their properties should directly inform and test our understanding of the early stages of galaxy evolution. In the past few years we have made great progress in identifying distant galaxies through deep observations with the largest optical and near-infra-red sensitive telescopes. We have identified with certainty over 100 galaxies which are seen when the Universe was no older than about 1 billion years old ( it is now 13.7 billion years old), and have identified candidates for galaxies seen at even earlier times. We currently have little understanding of their properties in any detail, having concentrated on their discovery and measuring the simplest of their properties and statistics. Almost all of the information we have on these systems comes from their ongoing star formation episodes which result in strong UV emission from short-lived massive stars. The bulk of the matter in these systems, whether baryons (ordinary matter) or dark matter, is not bright or detectable in the rest-frame ultra violet. Consequently, we have little or no information on the bulk of the material in and around these galaxies, severely limiting their use to develop and test models of early galaxy evolution. A new generation of instrumentation is just becoming available, instruments that will transform our ability to explore the properties of the galaxies and their environments in some detail. Using KMOS, a multi-object near-IR spectrograph which will be available on the VLT, and ALMA and other mm/sub-mm wave telescopes, we will determine accurate redshifts, dynamics and masses for the galaxies, determine whether they contain an appreciable number of the first generation of stars (as yet undetected) and search for signs of any material infalling onto the galaxies as part of their evolution. We will probe the properties of cool and cold gas, both atomic and molecular, that must be within the galaxies and in their surroundings if they are going to go on to form the largest galaxies that we see in the Universe today. By combining the results of all of these observational studies along with existing data on the same galaxies, we will develop a much more complete picture of how early galaxy evolution proceeds, a picture that will directly inform and challenge models of the key processes that leads to the formation of galaxies like our own Milky Way.

我们对宇宙的理解的核心是星系进化的话题。这些大型恒星，气体，灰尘和暗物质系统如何从大爆炸产生的几乎均匀的物质分布形成和进化的细节如何影响宇宙其余的特性如何发展。尽管有非常详细的理论思想，即如何形成星系形成的星系如何形成星系形成的多个不同且经常竞争的模型，但目前很少有可用于约束和测试这些模型的早期星系的观察测量值。对于测试这些模型特别重要的是对宇宙年轻时看到的星系的观察。看到的星系应该是今天看到的更成熟和更大的星系的相对原始的构件。鉴于此类系统可用于进化的有限时间，它们的演变不应特别复杂，因此它们的特性应直接告知和测试我们对银河发展早期阶段的理解。在过去的几年中，我们通过用最大的光学和近红色敏感望远镜的深度观察来识别遥远的星系取得了长足的进步。我们已经确定了超过100个星系，当宇宙年龄不超过10亿年（现在已有137亿年历史）时，并且已经确定了候选人在更早时期看到的星系。目前，我们对它们的属性几乎没有详细了解，因为他们专注于他们的发现并衡量其属性和统计数据的最简单。我们几乎所有有关这些系统的信息都来自其正在进行的恒星形成发作，从而导致短寿命巨星的紫外线发射强劲。这些系统中的大部分物质，无论是巴元（普通物质）还是暗物质，在其余框架的超紫色中都不明亮或可检测到。因此，我们几乎没有关于这些星系内和周围大部分材料的信息，从而严重限制了它们用于开发和测试早期星系进化的模型。新一代的仪器刚刚起到可用性，这些仪器将改变我们详细探索星系及其环境的特性的能力。使用KMO，将在VLT上可用，ALMA和其他MM/Sub-MM波望远镜上使用KMO，我们将确定星系的准确的红移，动态和质量，确定它们是否包含相当数量的恒星数量（尚未被发现）（如尚未被发现的），并搜索了任何迹象的迹象。如果要继续形成我们当今宇宙中我们看到的最大的星系，我们将探测原子和分子的凉爽和冷气的性质。通过将所有这些观察性研究的结果与相同星系上的现有数据相结合，我们将更加完整地了解早期星系演化的进行方式，这一图像将直接为关键过程提供和挑战关键过程，从而导致像我们自己的乳白色之类的星系形成。