Program: GS-2021B-Q-110

Lyman alpha blobs (LABs) are mysterious, giant (~100 kpc), glowing gas clouds in the distant universe. While we do not fully understand what makes most of them glow, their over-dense environment, strong clustering, and multiple embedded galaxies suggest that LABs may mark the site of proto-galaxy-groups falling into deeper protocluster potential wells. However, even the basic properties of LABs – their number density, environments, and cosmic evolution – are still not fully constrained. To obtain a large and representative LAB sample, we are conducting one of the most extensive narrowband surveys to search for LABs as well as Ly-alpha emitters and proto-clusters. Thanks to the depth and enormous survey area, we have already identified ~50 LAB candidates from the 1/10th of the planned survey! Using Gemini/GMOS, we propose to spectroscopically confirm the six LAB candidates with various properties. The deep optical spectra will allow us to (1) investigate blob’s energy source by searching for AGN signatures (e.g., C IV & He II), (2) explore if there is any evidence for large-scale kinetic motion of Ly-alpha-emitting gas, and (3) refine our newly-developed search techniques for LABs.