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

AST98-02658 Osmer PI正在进行与生产和使用大面积多色测量有关的四个项目。高质量、大面阵的ccd和具有多个ccd探测器的照相机的发展对观测宇宙学具有重要意义。现在用4米级别的望远镜可以测量许多平方度的天空，限制在大于或等于25 MAG的量级(回到宇宙不到现在年龄的10%的时代)。PI提出了四个项目：(1)寻找红移时的类星体，以确定它们何时首次可见，它们的空间密度演变有多快，以及它们与星系的形成有何关系。(2)研究红移为2的类星体的光度函数，使之降到与邻近活动星系核相似的绝对星等，从而限制它们在现在和更多发光类星体达到空间密度演化峰值之间的演化。(3)研究红移至3.5的星系的光学性质的演化；(4)研究类星体与星系在相同红移和绝对光度范围内的观测关系。PI已经开始了三次调查：其中两次调查的目标是红移为5的物体。第一次调查覆盖了1000°2的天空，第二次调查覆盖了50°2的天空。第二个调查是多彩的，使用B、V、I滤光片，最低限值为I=24 MAG。第三项调查也是多彩的，使用B、R、I滤镜。它覆盖了8度的天空，最小的星等为R=25.7毫克。第三次调查寻找红移为3.3的类星体。PI是在U，V超过3°2的第三次测量观测中添加的。***

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. ***