Tracing the Evolution of Galaxies

安德鲁·康诺利约翰·霍普金斯大学追踪星系的演化在过去的几年里，对星系演化的研究已经成为观测天文学中最令人兴奋和最具活力的领域之一。我们现在看到全球移动光度密度（即恒星形成率）从零红移到z为1.5的峰值迅速上升。在较高的红移中，恒星形成速率似乎普遍下降。这些都是定性描述。康诺利博士正在量化特定星系群的进化过程。他有一套统计技术，可以通过宽带光度法估算星系的红移。他希望能将观测到红移的星系数量从几千个增加到5万多个。然后，他将追踪星系光谱类型和形态的光度函数的演变。红移区间1z2的恒星形成活动是进化之谜中另一个缺失的部分。康诺利博士正在用哈勃太空望远镜进行一项发射线调查，以确定巴尔默线、氢的H（和OIII）线。这将在这个红移范围内得到第一个系统选择的星系样本。＊＊＊

AST 98-02978 Andrew Connolly Johns Hopkins University Tracing the evolution of galaxies Over the last few years the study of the evolution of galaxies has emerged as one of the most exciting and dynamic areas of observational astronomy. We now see a rapid rise in the global comoving luminosity density (i.e., star formation rate) from a redshift of zero to a peak about z of 1.5. At higher redshifts there appears to be a general decline in the star formation rate. These are qualitative descriptions. Dr. Connolly is quantifying how particular galaxy populations evolve. He has a suite of statistical techniques for estimating the redshifts of galaxies from broadband photometry. He expects to increase the number of galaxies with observed redshift from a few thousand to more than fifty thousand. He will then trace the evolution of the galaxy luminosity function of spectral type and morphology. Star formation activity in the redshift interval 1 z 2 is another missing piece of the evolutionary puzzle. Dr. Connolly is undertaking an emission line survey with the Hubble Space Telescope to identify the Balmer line, H ( of hydrogen as well as OIII lines. This will derive the first systematically selected sample of galaxies in this redshift range. ***