Presentation #341.07 in the session “Galaxy Quenching”.
E+A galaxies are post-starburst galaxies that have undergone a recent, complete quenching of their star formation. We have analyzed a color-constrained sample of 181 galaxies from the Sloan Digital Sky Survey (SDSS DR 16) within a 77.5 arcmin radius of the center of the Leo cluster of galaxies (Abell 1367; J114436.5+194532) to identify and survey the E+A galaxies and E+A candidates in the cluster. All of these galaxies are within 3000 km/s of Leo’s redshift of z=0.022. Within this sample, we classified 52 of these galaxies as E+A galaxies and candidates based on their spectral shapes, u-r color, lack of Hα emission, and higher-order hydrogen Balmer absorption. We further subdivide that group into “blue” (4 objects) and “green” (48 objects) E+As and candidates. An additional 51 of these galaxies were classified as “ambiguous” E+A candidates, which have spectral characteristics that suggest they are E+As but which we cannot confidently confirm due to either a low S/N ratio or the absence of components of E+A galaxy spectra. Our preliminary results show high concentrations of E+As in Leo’s northwest and southeast subcluster regions. This work was supported by the Alfred P. Sloan Foundation via the SDSS-IV Faculty and Student Team (FaST) initiative, ARC Agreement SSP483, and by NSF grants AST-1852355, 1852360, 1460939, and 1460860 to the American Museum of Natural History and CUNY College of Staten Island.