Analysis of a Survey for Ultra Low Surface Brightness Galaxies

[901663] Stacy mcgough大量的研究表明，观测到的星系表面亮度和大小的范围是由观测选择决定的——主要是对表面亮度较低的星系的区分——而不是由星系的内在特性决定的。为了确定宇宙的光度密度，时空几何和星系的演化需要一个完整的星系表面亮度和大小范围。McGaugh博士领导的团队已经完成了一项覆盖100度的CCD成像调查，该调查旨在发现表面亮度非常低的星系。该调查对R波段表面亮度敏感，mR = 27.4 arcsec-2或更高。他的团队正在利用这个数据库进行几项辅助研究。从这次调查中编目的星系被用来解决银河系外天文学和宇宙学中的一些突出问题。这包括星系的本征表面亮度分布、低表面亮度星系对星系光度和质量函数的贡献、嵌在暗物质晕中的盘的稳定性、盘内恒星形成阈值以及星系盘的光学边缘。

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.