New insight on the galaxy formation process from the star formation histories of satellite galaxies

从卫星星系的恒星形成历史对星系形成过程的新认识

• 批准号: 311797-2013
• 负责人: Balogh, Michael
• 金额: $ 2.33万
• 依托单位: University of Waterloo
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2016
• 资助国家: 加拿大
• 起止时间: 2016-01-01 至 2017-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=595019
• 关键词: New; insight; galaxy; formation; process

One of the great mysteries is how galaxies assembled into the myriad shapes and sizes we see today. Our own Milky Way has a fascinating, complex structure including spiral arms, a central bar and bulge, a supermassive black hole, Galactic fountains and high velocity clouds. And while the Milky Way is not unusual, most galaxies are thousands of times less massive; some are hundreds of times larger. In fact, no two galaxies look the same, which is something of a puzzle since the Universe itself arose out of the Big Bang in a very uniform state. Moreover, structure growth is dominated by mysterious dark matter, which interacts only via gravity and thus should look similar on all scales. The explanation for the appearance of galaxies lies in the complex interplay between hot gas, cold gas, and stars. Enormous amounts of energy are exchanged between these phases, as supernovae explode, giant black holes accrete gas, and molecular clouds cool down to form new stars. Advanced galaxy formation theory gives us a good framework with which to interpret our observations, but the model relies on many approximations and assumptions that are poorly constrained by current data. This research will focus on the evolution of "satellite galaxies", which are systems that orbit larger galaxies. There is no self-consistent explanation for many of their observed characteristics, and it is not understood why they should have evolved so differently from the host galaxy around which they orbit. One of the main limitations to progress has been the lack of good data on satellite galaxies at earlier times in the Universe's history. Through ambitious observation using new instrumentation, and advanced modeling techniques, this research will result in a monumental leap forward in our understanding of these interesting and important galaxies. Reconciling the existing conflicts with models will lead to new discoveries about the fundamental physical processes responsible for the formation and evolution of galaxies.

最大的奥秘之一是星系如何组装成我们今天看到的无数形状和尺寸。我们自己的银河系具有令人着迷，复杂的结构，包括螺旋臂，中央酒吧和凸起，超大型黑洞，银河喷泉和高速速度云。尽管银河系并不罕见，但大多数星系的巨大数量降低了数千倍。有些大数百倍。实际上，没有两个星系看起来相同，这是一个难题，因为宇宙本身以非常统一的状态出现了大爆炸。此外，结构生长由神秘的暗物质主导，该暗物质仅通过重力进行相互作用，因此在所有尺度上都应该看起来相似。星系出现的解释在于热气，冷气和恒星之间的复杂相互作用。这些相之间交换了大量的能量，因为超新星爆炸，巨大的黑孔积聚气体和分子云冷却以形成新的恒星。先进的星系形成理论为我们提供了一个很好的框架来解释我们的观察结果，但是该模型依赖于许多受当前数据限制的近似值和假设。这项研究将集中于“卫星星系”的演变，该系统是轨道范围更大星系的系统。对于他们的许多观察到的特征，没有自一致的解释，也不理解为什么它们应该与围绕的宿主银河系如此不同。进步的主要局限性之一是在宇宙历史上早期缺乏有关卫星星系的良好数据。通过使用新仪器和先进的建模技术的雄心勃勃的观察，这项研究将在我们对这些有趣而重要的星系的理解中带来巨大的飞跃。将现有冲突与模型进行调和将导致有关导致星系形成和演变的基本物理过程的新发现。