CAA Seminar (Dec.19,2016): Cosmic Mammoth - Mapping the Most Massive Large-scale Structures in the early Universe
Source:Seminars Date:2016-12-28

Time: 10:30--11:30,19th December.

Address: CAA lecture Hall,Jianchuan Road 955(我享我家大厦2楼)


Title: Cosmic Mammoth - Mapping the Most Massive Large-scale Structures in the early Universe

Speaker: Dr.Cai Zheng (UCSC)

Abstract:

In this talk, I will present a novel survey of the most massive overdensities of galaxies in the peak of cosmic star formation and QSO activities (z=2--4). These structures are traced by the strongest intergalactic Hi (Lyman-alpha) absorption on large scales of 10-30 Mpc. Our cosmological simulations show a strong correlation between the optical depth of Ly-alpha absorption and mass overdensities. I will present the survey of the strong Hi absorption due to intergalactic medium (IGM) overdensities, and further present our discovery of a sample of extremely massive overdensies at z~2.3 by utilizing LBT, Keck, KPNO-4m, and CFHT. I will further discuss the discovery of largest Lyman alpha nebulae in these fields, which are unique laboratories to study the IGM-galaxy interactions. In the end, I will talk about the future prospects. I will stress how incoming surveys, such as DESI and Subaru/Prime Focus Spectrograph (PFS), will greatly help our MAMMOTH survey; and how novel instruments, especially the imager-slicer IFS and TMT/WFOS, will solve fundamental questions in galaxy/structure formation. I will further talk about a few exciting science/instrumentation opportunities that can be achieved by collaborating with Shanghai Jiaotong experts.