Analysis of a Survey for Ultra Low Surface Brightness Galaxies

9901663斯泰西·麦高许多研究已经表明，观测到的星系表面亮度和大小的范围是由观测选择限制的-主要是对低表面亮度星系的歧视-而不是由星系的内在属性。 为了确定宇宙的亮度密度、时空几何和星系的演化，需要全范围的星系表面亮度和大小。McGaugh博士领导的一个团队已经完成了一项覆盖100 deg 2的CCD成像调查，旨在发现表面亮度非常低的星系。 该调查是敏感的R波段表面亮度的mR = 27.4 mag arcsec-2或更好。 他的团队正在使用这个数据库进行几项辅助研究。 从这次巡天中编目的星系被用来解决河外天文学和宇宙学中一些悬而未决的问题。 包括星系的内禀表面亮度分布、低表面亮度星系对星系光度和质量函数的贡献、暗物质晕中暗物质盘的稳定性、暗物质盘中星星形成阈值以及暗物质盘的光学边缘。

9901663 Stacy McGaughNumerous studies have now shown that the range of observed galaxy surface brightnesses and sizes is bounded by observational selection - principally discrimination against galaxies of low surface brightness - and not by the intrinsic properties of galaxies. To determine the luminosity density of the Universe, the geometry of space-time and the evolution of galaxies requires a full range of galaxy surface brightnesses and sizes. Dr. McGaugh led a team that has completed a CCD imaging survey covering 100 deg2 designed to discover galaxies having very low surface brightness. The survey is sensitive to an R band surface brightness of mR = 27.4 mag arcsec-2 or better. His team is conducting several ancillary studies using this database. Galaxies cataloged from this survey are used to address a number of outstanding issues in extragalactic astronomy and cosmology. These include the intrinsic surface brightness distribution of galaxies, the contribution of low surface brightness galaxies to the galaxy luminosity and mass functions, the stability of disks imbedded in dark matter halos, star formation thresholds in disks and the optical edges of galaxy disks.