Nottingham Astronomy Rolling Grant 2011 - 2016

诺丁汉天文学滚动资助 2011 - 2016

• 批准号: ST/I001212/1
• 负责人: Alfonso Aragon-Salamanca
• 金额: $ 234.37万
• 依托单位: University of Nottingham
• 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%2FI001212%2F1
• 关键词: Nottingham; Astronomy; Rolling; Grant; 2011

Astronomical research in the School of Physics & Astronomy at the University of Nottingham is focused on studying the formation and evolution of galaxies. These gravitationally-bound collections of stars, gas, dust and dark matter are some of the most beautiful objects in the Universe, and a major theme in modern astronomy involves trying to understand how they came into existence. To tackle this complex question, we will draw on the full range of tools at our disposal, involving everything from large-scale numerical simulations to detailed observational studies of individual galaxies using ground- and space-based observatories. One key issue is how galaxies, once formed, alter their appearance over time. For example, we are studying how spiral galaxies can turn into featureless lenticular systems, seeking to understand the physical process that quenches their star formation and erases their spiral arms. Similarly, we are exploring the processes by which the spectacular bar features at the centres of many spiral systems can appear and disappear, and what effect these changes have on the surrounding galaxy. We are investigating both internal and environmental processes that can change the appearance of a galaxy, to obtain an integrated picture of how galaxy transformations occur. Our work will combine detailed studies of nearby systems, searching for archaeological clues as to how they were made, and direct observations of evolution taking place over the last seven billion years in the history of the Universe. These studies of galaxies in transformation are complemented by observations of even more distant systems, which capture galaxies in the act of initial formation. Major puzzles remain unresolved at these early stages, such as the mechanism responsible for terminating star-formation in massive galaxies. We are tackling these problems with a two-pronged approach. First, surveys of unprecedented sensitivity allow us to determine the dependence of galaxy evolution on external factors, such as the local environment or the mass of the surrounding dark matter halo. Second, studies using the new instruments on the Hubble Space Telescope and on large ground-based telescopes allow the structural properties of individual galaxies near the beginnings of their lives to be dissected in detail. However, studying only visible and near-infrared light cannot provide a complete picture. About half the energy emitted by galaxies is absorbed by interstellar dust, concealing their true structure. Studying this 'stolen starlight,' which is re-radiated in the far infrared, reveals this hidden side of galaxy evolution. To-date, it has been impossible to understand this vital element of the story, as we have not been able to obtain the far-infrared observations that would recapture this lost light over a representative area of the sky. The Herschel Space Observatory, launched in 2009, now allows us to obtain the necessary data. The ATLAS survey, in which we are playing a leading role, is the widest area survey that Herschel will conduct, and will far surpass any other ground- or space-based survey in this part of the spectrum for many years to come. It will characterise the dust content and obscured star formation for ~200,000 galaxies spread over most of cosmic history, revealing the secrets of this hidden aspect of galaxy evolution. The final aspect to this research programme involves using the University's supercomputing facilities to simulate the formation of galaxies in the full cosmological context of the surrounding Universe. By comparing the results of such simulations with the extensive observational programmes, we will be able to check our understanding of the physical processes driving galaxy evolution. We will also use the observations of the earliest epochs to set the initial conditions for our simulations, to see whether we can follow galaxies' subsequent evolution to the present-day.

诺丁汉大学物理与天文学学院的天文学研究重点是研究星系的形成和演化。这些由恒星、气体、尘埃和暗物质组成的引力集合是宇宙中最美丽的物体之一，现代天文学的一个主要主题是试图理解它们是如何存在的。为了解决这个复杂的问题，我们将利用我们可以使用的各种工具，从大规模的数值模拟到使用地面和空间观测站对单个星系进行详细的观测研究，无所不包。一个关键的问题是，星系一旦形成，随着时间的推移会如何改变它们的外观。例如，我们正在研究螺旋星系如何变成无特征的透镜系统，试图了解使其恒星形成熄灭并抹去其旋臂的物理过程。同样，我们正在探索许多螺旋星系中心壮观的条形特征可能出现和消失的过程，以及这些变化对周围星系的影响。我们正在研究内部和环境过程，这些过程可以改变星系的外观，以获得星系如何发生变化的综合图像。我们的工作将结合对附近系统的详细研究，寻找它们是如何形成的考古学线索，以及对过去70亿年宇宙历史上发生的进化的直接观察。这些对转化中的星系的研究得到了对更遥远的系统的观测的补充，这些系统捕捉到了星系的初始形成行为。在这些早期阶段，主要的谜题仍然没有解决，比如终止大质量星系中恒星形成的机制。我们正以双管齐下的方式处理这些问题。首先，史无前例的灵敏度调查使我们能够确定星系演化对外部因素的依赖，例如局部环境或周围暗物质晕的质量。其次，使用哈勃太空望远镜和大型地面望远镜上的新仪器进行研究，可以详细分析单个星系在生命开始时的结构特性。然而，只研究可见光和近红外光并不能提供完整的图像。星系发射的能量大约有一半被星际尘埃吸收，掩盖了它们的真实结构。研究这一被窃取的星光，在远红外中重新辐射，揭示了星系演化的这一隐藏的一面。到目前为止，我们还不可能理解这个故事的这一关键要素，因为我们还无法获得能够在具有代表性的天空区域重新捕捉到失去的光线的远红外观测。2009年发射的赫歇尔空间天文台现在允许我们获得必要的数据。我们在其中发挥主导作用的ATLAS调查是赫歇尔将进行的范围最广的调查，在未来许多年里将远远超过这部分频谱中的任何其他地面或天基调查。它将描述分布在宇宙历史大部分时期的约200,000个星系的尘埃含量和遮挡恒星的形成，揭示星系演化这一隐藏方面的秘密。这项研究方案的最后一个方面涉及利用该大学的超级计算设施在周围宇宙的整个宇宙学背景下模拟星系的形成。通过将这种模拟的结果与广泛的观测计划进行比较，我们将能够检查我们对驱动星系演化的物理过程的理解。我们还将利用对最早纪元的观测来为我们的模拟设定初始条件，看看我们是否可以跟踪星系的后续演化到现在。

项目成果

New Measurements of the Ionizing Ultraviolet Background over 2 < z < 5 and Implications for Hydrogen Reionization

• DOI: 10.1093/mnras/stt1610
• 发表时间: 2013-07
• 期刊: Monthly Notices of the Royal Astronomical Society
• 影响因子: 4.8
• 作者: G. Becker;J. Bolton

Galaxy And Mass Assembly (GAMA): Linking Star Formation Histories and Stellar Mass Growth

• DOI: 10.1093/mnras/stt1011
• 发表时间: 2013-06
• 期刊: Monthly Notices of the Royal Astronomical Society
• 影响因子: 4.8
• 作者: A. Bauer;A. Hopkins;M. Gunawardhana;E. Taylor;E. Taylor;I. Baldry;S. Bamford;J. Bland-Hawthorn;S. Brough;Michael J. I. Brown;M. Cluver;M. Colless;M. Colless;C. Conselice;S. Croom;S. Driver;S. Driver;C. Foster;D. Jones;M. Lara-López;J. Liske;Á. López-Sánchez;Á. López-Sánchez;J. Loveday;P. Norberg;M. Owers;K. Pimbblet;A. Robotham;A. Robotham;A. Sansom;R. Sharp

GAMA/H-ATLAS: linking the properties of submm detected and undetected early-type galaxies - I. z = 0.06 sample

GAMA/H-ATLAS：将已检测到的亚毫米级星系和未检测到的早期型星系的特性联系起来 - I. z = 0.06 样本

• DOI: 10.1093/mnras/stt310
• 发表时间: 2013
• 期刊: Monthly Notices of the Royal Astronomical Society
• 影响因子: 4.8
• 作者: Agius N