Optical Observations of the ACT Sky Region

这个项目是使用新的南部非洲大望远镜（SALT）减少和分析四个波段漂移扫描调查数据的更大努力的一部分，该地区被选中覆盖与即将到来的阿塔卡马宇宙望远镜（ACT）微波背景图相同的天空区域。通过从这些扫描中制作星系目录，将有可能确定光度红移，并选择星系团成员进行光谱跟踪，这两项都将为ACT通过Sunyaev-Zel'dovich失真对星系团的观测增加相当大的价值。星系团可以为结构的增长提供强有力的约束，包括中微子质量和暗能量状态方程，本研究有助于提供充分利用ACT星系团进行宇宙学研究所需的光学数据，并约束宇宙的近期膨胀历史。这将是SALT望远镜的一个高知名度项目，提高SALT特别是非洲科学的形象，并为非洲学生和研究人员带来更多的合作和科学机会。它还包括学生研究人员，并与智利的ACT工作联系起来。

AST-0546035KosowskyThis project is part of a larger effort to reduce and analyze the data from a drift scan survey in four bands using the new Southern African Large Telescope (SALT), in an area chosen to cover the same sky region as the forthcoming Atacama Cosmology Telescope (ACT) microwave background maps. By making a galaxy catalog from these scans, it will be possible to determine photometric redshifts, and to choose cluster members for spectroscopic follow-up, both of which will add considerable value to the ACT observations of galaxy clusters via the Sunyaev-Zel'dovich distortion. Galaxy clusters can provide strong constraints on the growth of structure, including the neutrino mass and the dark energy equation of state, and this research helps to provide the optical data necessary to exploit the ACT clusters fully for cosmology, and constrain the recent expansion history of the Universe.This will be a high-visibility project for the SALT telescope, raising the profile of SALT in particular and science in Africa in general, and leading to expanded collaborative and scientific opportunities for African students and researchers. It also involves student researchers, and connects to ACT efforts in Chile.