Assembling the big picture of nearby galaxies

组装附近星系的大图

• 批准号: 342635-2013
• 负责人: Barmby, Pauline
• 金额: $ 1.97万
• 依托单位: University of Western Ontario
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2014
• 资助国家: 加拿大
• 起止时间: 2014-01-01 至 2015-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=549643
• 关键词: Assembling; big; picture; nearby; galaxies

Galaxies are the building blocks of the universe, the place where stars and planets are born. The inner life of galaxies is complex: stars are formed from dense, cold gas, spend their finite lifetimes fusing hydrogen into helium and heavier elements, and then die, returning some of the processed material to space where the cycle begins again. There is a complicated interplay between stars, interstellar gas and dust, the haloes of dark matter that surround galaxies and the giant black holes that live at their centres. The rate of new star formation depends on the physical properties of the gas, which in turn depend on the past history of star formation, which affects and can be affected by the central black hole. In establishing the stories of galaxies, important questions include whether models can reconstruct unique past histories, how the formation of new stars varies within galaxies, and how the mass and star formation of galaxies can best be measured. The huge variations in pressure, temperature, and density in the various galaxy components mean that different parts of galaxies absorb and emit light at many different wavelengths. While astronomers previously tended to specialize in observations made at a particular wavelength, it is now clear that we need a multi-wavelength approach to assemble the full picture of how galaxies arrived at their present diversity of states. In nearby galaxies the available observations can probe both the present and past of these complex ecosystems in exquisite detail, but only if we can find new and better ways to manage and exploit the data. This program will develop the tools and techniques to compare the internal structures of galaxies to each other and to the increasingly-sophisticated models which describe the interplay between stars, gas, dust, black holes, and dark matter. This will enable the derivation of detailed histories of nearby galaxies, an important part of the quest to understand the Milky Way's---and our own---place in the universe. The tools and training developed in this program will be transferable to other applications and enable astrophysicists to contribute to other areas of "Big Data" science.

星系是宇宙的基石，是恒星和行星诞生的地方。星系的内部生命是复杂的：恒星是由致密的冷气体形成的，在它们有限的生命周期中，将氢融合成氦和更重的元素，然后死亡，将一些经过处理的物质送回太空，在那里循环再次开始。恒星、星际气体和尘埃、环绕星系的暗物质晕和位于星系中心的巨大黑洞之间存在着复杂的相互作用。新恒星形成的速度取决于气体的物理性质，而气体的物理性质又取决于恒星形成的过去历史，而过去的历史影响着中心黑洞，也可能受到中心黑洞的影响。在建立星系的故事中，重要的问题包括模型是否可以重建独特的过去历史，星系中新恒星的形成如何变化，以及如何最好地测量星系的质量和恒星形成。不同星系组成部分在压力、温度和密度上的巨大差异意味着星系的不同部分吸收和发射出许多不同波长的光。虽然天文学家以前倾向于专门研究特定波长的观测，但现在很清楚，我们需要一种多波长的方法来收集星系如何达到目前多样性状态的全貌。在邻近的星系中，现有的观测可以非常详细地探测这些复杂生态系统的现在和过去，但前提是我们能找到新的、更好的方法来管理和利用这些数据。这个项目将开发工具和技术来比较星系的内部结构，并与描述恒星、气体、尘埃、黑洞和暗物质之间相互作用的日益复杂的模型进行比较。这将使我们能够推导出附近星系的详细历史，这是了解银河系——以及我们自己——在宇宙中的位置的重要组成部分。在这个项目中开发的工具和培训将被转移到其他应用中，使天体物理学家能够为“大数据”科学的其他领域做出贡献。