The coevolution of massive compact ellipticals and their black holes at high redshift

本计画提出详细研究大质量致密演化椭圆星系及其高红移黑洞的起源。这些星系的星星形成率非常低，比现在的椭圆星系小三到五倍，质量密度比低红移的星系高一到两个数量级。我们将首次使用次千秒差距分辨率的宇宙学“变焦”模拟的统计样本的大规模星系的宇宙学量，以解决两个基本的物理问题：1）如何在大规模的高红移椭球体黑洞的增长和过程是负责终止星星形成在这些系统？它主要是来自一个中心超大质量黑洞的反馈，来自大质量恒星爆发的风，还是仅仅是非常有效的气体消耗或组合？2)为什么高红移椭圆星系如此紧凑？是什么推动了其尺寸的快速演化？有强有力的理论证据表明，较小的（气体贫乏）合并是更重要的强大的演化的大小和密度比主要的合并，特别是在高红移的大质量星系。我们将详细探讨这种增长机制。在融资期结束时，我们希望能够回答这两个问题。

This project proposes a detailed investigation of the origin of massive compact evolved elliptical galaxies and their black holes at high redshift. These galaxies have very low star formation rates, are three to five times smaller than present day ellipticals and have one to two orders of magnitude higher mass densities than their low redshift counterparts. We will, for the first time, use sub kiloparsec resolution cosmological ”zoom” simulations of a statistical sample of massive galaxies in a cosmological volume to address two fundamental physical questions: 1) How do black holes in massive high redshift spheroids grow and which process is responsible for the termination of star formation in these systems? Is it mainly feedback from a central super-massive black hole, winds from a massive starburst or simply very efficient gas consumption or a combination? 2) Why are the high redshift ellipticals so compact and what is the main driver for the rapid size evolution? There is strong theoretical evidence that minor (gas poor) mergers are more important for the strong evolution in size and density than major mergers, in particular for massive galaxies at high redshift. This growth mechanism will be explored in detail. At the end of the funding period we expect to be able to answer both questions.