The group environment: a key to galaxy evolution and quasar activity

附近质量最大的星系在宇宙当前年龄的四分之一到一半的时候建立了它们的大部分恒星和中心的超大质量黑洞。这些过程的同时代时间，以及黑洞质量和它们的宿主星系之间明显固定的关系，表明了这两个现象之间的联系。我提出的研究计划通过关注黑洞增长和星系演化的物理过程和星系团环境，解决了黑洞增长和星系演化的一个有趣的交叉问题，如下所列的三个项目中所概述的那样。 (1)确定类星体宿主星系会发生什么：作为类星体活跃增长的黑洞所在的星系内气体的运动直接影响到燃料过程。换句话说，类星体是由两个富含气体的星系戏剧性地合并引发的，还是更微妙的星系相互作用是气体流入原子核的原因？ (2)理解类星体反馈：对类星体尘埃风的计算机模拟提供了测量流出的结构和速度的可能性。有了这两个重要参数，就可以确定风的动能--也就是它们影响银河系主机的可能性。 (3)致密星系的核和恒星群的特征：本宇宙致密星系显示出从活跃的恒星形成到静止的快速演化的证据，因为即使是微妙的星系相互作用也通过触发恒星的形成加强了气体的处理。找到恒星的年龄并凝视银河系中心将开启对这些系统中恒星积累的研究。 这三个项目结合在一起形成了一个连贯的计划，用于研究作为发光类星体的超大质量黑洞的增长与大质量星系中恒星的形成之间的关系，这些过程是在群环境中孕育的。

The most massive nearby galaxies built up the bulk of their stars and their central supermassive black holes at a time when the Universe was a quarter to a half its current age. The coeval timing of these processes and the apparently fixed relationship between the masses of black holes and their host galaxies point towards a connection between these two phenomena. My proposed research program addresses an intriguing intersection of black hole growth and galaxy evolution by focusing on the physical processes and the galaxy group environment that link them as outlined in the three projects listed below. (1) Determining What Happens to a Quasar Host Galaxy: The motions of gas within a galaxy hosting a black hole actively growing as a quasar directly bear on the fueling process. In other words, was the quasar triggered by a dramatic merger of two gas-rich galaxies or were more subtle galaxy interactions the cause of the inflow of gas to the nucleus? (2) Understanding Quasar Feedback: Computer simulations of the dusty winds from quasars offer the potential to measure the structure and velocity of the outflows. With these two important parameters, the kinetic energy of the winds - and therefore their potential to affect their galaxy hosts - can be determined. (3) Characterizing Nuclei and Stellar Populations in Compact Group Galaxies: Compact group galaxies in the local Universe show evidence for rapid evolution from actively star forming to quiescent as the effects of even subtle galaxy interactions enhance the processing of gas through triggered star formation. Finding the ages of the stars and peering into the galaxy centres will open up the study of stellar buildup in these systems. These three projects combined form a coherent program for investigating the relationship between the growth of supermassive black holes as luminous quasars and the build-up of stars in massive galaxies, processes fostered in the group environment.