"The seeds of galaxy formation, obscured star formation at high redshift, and the local fossil record of galaxy formation."

“星系形成的种子，高红移下模糊的恒星形成，以及星系形成的当地化石记录。”

• 批准号: 418765-2012
• 负责人: Chapman, Scott
• 金额: $ 4.37万
• 依托单位: Dalhousie University
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2015
• 资助国家: 加拿大
• 起止时间: 2015-01-01 至 2016-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=573812
• 关键词: seeds; galaxy; formation; obscured; star

Observational cosmology is an attempt to understand the processes which initiated the universe we live in, and how the rich and complex structure in the present-day universe formed and evolved. My research focuses on studying both the fundamental physics of cosmology via the Cosmic Microwave Background (CMB) and measurements of structure on very large scales, down to the details of galaxy evolution and the complex physics which manifests on small scales. There are many unanswered questions, starting from how the primordial density fluctuations in the very early universe inflated to produce the observed distribution of structure and galaxies, all the way to how environment drives galaxy evolution. Studying the Sub-millimetre Galaxies (SMGs) in particular in the distant universe gives us insight into the peak epoch in which massive galaxies were forming the bulk of their stars. This leads to a host of questions, such as whether massive galaxies form in a single burst of star formation or is their growth extended over time. My laboratory is involved in several experiments aimed at studying SMGs as well as the CMB: the South Pole Telescope (SPT) is a 10 metre telescope we have been actively involved with for the past two years, simultaneously gaining new information on the brightest SMGs, galaxy clusters (the Sunyaev-Zeldovich effect), and primary CMB. The POLARization of the Background Radiation (POLARBeaR) experiment focuses on the polarized B-mode radiation from the CMB - the `smoking gun' of the Early Universe inflationary epoch in the first 10^-38sec after the Big Bang. We are partners with Berkeley and Chicago in these experiments and take an active role in both leading areas of the science and in instrumentation development. These experiments will provide important new results during the period of this grant. I'm also active in the space-based Herschel telescope studies of distant SMGs, with large PI and co-I allocated projects in my Herschel-HerMES, LESS/SHRUGS, and SPT collaborations, and I am working towards various projects with the newly commissioned SCUBA-2 camera on the Canada/UK/Dutch JCMT telescope. My approach to research in this area is multifaceted, combining a number of different yet complementary studies. I work on detailed studies of small numbers of galaxies, which can teach us about very specific physics driving their evolution; but I also undertake statistical studies of large samples, which provides information on global proerties of galaxies and the overall trends in galaxy evolution. By studying galaxies which exist in isolation as well as those evolving in unique high density regions I can constrain the role of the environment in forming galaxies. I also sample the entire electromagnetic spectrum, though with a strong focus on the relatively unexplored infrared regime. Such mulitwavelength data are crucial as observations at different wavelengths probe different physical processes which are relevant to galaxy evolution. For example, the infrared allows us to study the current star formation in a galaxy, while optical light gives us information on (amongst other things) previous star formation. Using these complementary techniques and the new generation of telescopes and detectors, I, along with my team of graduate students and postdocs, will shed light on the process of cosmology and galaxy evolution.

观测宇宙学试图了解我们所生活的宇宙的形成过程，以及当今宇宙丰富而复杂的结构是如何形成和演化的。我的研究重点是通过宇宙微波背景（CMB）研究宇宙学的基础物理和大尺度结构的测量，直至星系演化的细节和小尺度上表现的复杂物理。还有许多悬而未决的问题，从早期宇宙中的原始密度波动如何膨胀以产生观察到的结构和星系分布，一直到环境如何驱动星系演化。研究亚毫米星系（SMG），特别是遥远宇宙中的亚毫米星系，可以让我们深入了解大质量星系形成其恒星的高峰时期。这引发了一系列问题，例如大质量星系是否是在一次恒星形成爆发中形成的，或者它们的生长是否会随着时间的推移而延长。 我的实验室参与了多项旨在研究 SMG 和 CMB 的实验：南极望远镜 (SPT) 是一台 10 米望远镜，我们在过去两年中一直积极参与其中，同时获取有关最亮 SMG、星系团（Sunyaev-Zeldovich 效应）和主 CMB 的新信息。背景辐射的极化 (POLARBeaR) 实验重点研究来自宇宙微波背景 (CMB) 的极化 B 模式辐射——宇宙大爆炸后第一个 10^-38 秒内早期宇宙暴胀时期的“铁证”。我们是伯克利分校和芝加哥大学在这些实验中的合作伙伴，并在科学的领先领域和仪器开发方面发挥着积极的作用。这些实验将在本次资助期间提供重要的新成果。 我还积极参与遥远 SMG 的天基赫歇尔望远镜研究，在我的 Herschel-HerMES、LESS/SHRUGS 和 SPT 合作中拥有大型 PI 和共同分配的项目，并且我正在使用加拿大/英国/荷兰 JCMT 望远镜上新委托的 SCUBA-2 相机开展各种项目。 我在这一领域的研究方法是多方面的，结合了许多不同但互补的研究。我致力于对少量星系的详细研究，这可以让我们了解驱动星系演化的非常具体的物理原理；但我也进行大样本的统计研究，提供有关星系整体特性和星系演化总体趋势的信息。通过研究孤立存在的星系以及在独特的高密度区域中演化的星系，我可以限制环境在形成星系中的作用。我还对整个电磁频谱进行了采样，但重点关注相对未经探索的红外区域。这种多波长数据至关重要，因为不同波长的观测可以探测与星系演化相关的不同物理过程。例如，红外线使我们能够研究星系中当前的恒星形成，而光学则为我们提供有关（除其他外）先前恒星形成的信息。利用这些互补的技术以及新一代的望远镜和探测器，我和我的研究生和博士后团队将阐明宇宙学和星系演化的过程。