Colloquium on Apr. 2, 2020

Compact galaxy systems in Sloan Digital Sky Survey and LAMOST spectral survey

Speaker: Shiyin Shen (SHAO)

Venue: Video Conference

Time: 3:00 PM, Thursday, Apr. 2, 2020

Abstract: 

In this talk, I will first introduce the complementary galaxy sample in the LAMOST spectral survey, which targets the low redshift galaxies without redshift measurements in the main galaxy sample of the Sloan Digital Sky Survey（SDSS） due to the fiber collision effect. These galaxies are mainly in the compact galaxy systems, e.g. galaxy pairs, triplets and compact galaxy groups, which are ideal labs for studying the galaxy-galaxy interaction and merging process. By combining the complementary galaxy sample with the SDSS main galaxy sample, we have built the largest and the most complete galaxy pair and compact galaxy group sample to date. With the large galaxy pair sample, we have first time quantified how two galaxies are paired with a novel statistical approach. With kinematical data from integral field spectroscopy, we may further quantify the merging phase of individual galaxy pairs. With the spectroscopic redshifts of the group members, we first time characterize the dynamical properties of the compact galaxy groups and so that reveal the connection between the compact galaxy groups and the normal galaxy groups.