The Evolution of Quasars and Galaxies: Large-Area Multicolor Surveys

PI正在进行四个与生产和使用大面积多色测量有关的项目。高质量、大画幅CCD和多CCD探测器相机的发展对观测宇宙学具有重要意义。现在可以用4米级的望远镜来观测天空的许多平方度，以限制大于或等于25等的星等（回到宇宙年龄不到现在的10%的时代）。PI提出了四个项目：(1)在红移时搜索类星体，以确定它们何时首次出现，它们的空间密度演变有多快，以及它们与星系形成的关系。(2)研究红移=2的类星体的光度函数，直至与附近的agn相似的绝对星等，从而限制它们从现在到更明亮的类星体在其空间密度演化中达到峰值的时代之间的演化。(3)研究红移3.5以内星系光学性质的演化；(4)研究类星体与相同红移和绝对光度范围内星系的观测关系。PI已经开始了三次调查：其中两次调查的目标是红移5的天体。第一个覆盖1000度的天空，第二个覆盖50度的天空。第二次调查是多色的，使用B， V， I滤光器，直到I = 24等的极限。第三次调查也是多色的，使用B， R， I滤光器。它覆盖了8度2的天空，极限星等R = 25.7等。第三次巡天搜寻红移值为3.3 5.0的类星体。PI加入了第三次在U，V， 3°2以上的观测。＊＊＊

AST 98-02658 Osmer The PI is undertaking four projects related to production of and use of large area multicolor surveys. The development of high quality, large format CCDs and cameras with multiple CCD detectors has been important to observational cosmology. It is now possible to survey many square degrees of the sky with 4 meter class telescopes to limiting magnitudes greater than or equal to 25 mag (back to epochs when the universe was less than 10% of its present age). The PI proposes four projects: (1) to search for quasars at redshift5 to determine when they first become visible, how rapidly their space density evolves, and how they relate to the formation of galaxies. (2) to investigate the luminosity function of quasars at redshift=2 down to absolute magnitudes similar to those of nearby AGNs, thereby constraining their evolution between the present and the epoch when more luminous quasars reach a peak in the evolution of their space density. (3) to study the evolution of the optical properties of galaxies at redshifts up to 3.5, and (4) to study the observational relationship between quasars and galaxies over the same range in redshift and absolute luminosity. The PI has begun three surveys: Two of the surveys target objects with redshift 5. The first one covers 1000 deg2 of sky, the second one covers 50 deg2 of sky. This second survey is multicolor and uses B, V, I filters down to a limiting magnitude of I = 24 mag. The third survey is also multicolor and uses B, R, I filters. It covers 8 deg2 of sky down to a limiting magnitude of R = 25.7 mag. This third survey searches for quasars with 3.3redshift5.0. The PI is adding to the third survey observations in U,V over 3 deg2. ***