Beyond the Break in the Galactic Stellar Disk: A Search for Red Clump Giants

Using data from 2MASS, AllWISE, Gaia, and Pan-STARRS, we analyze a sample of sources likely to be “red clump giants”—low mass, moderate metallicity, helium core-burning red giants. These stars have a tight range of luminosity and are used as standard candles to create a three-dimensional map of the stellar density of the outer section R > 10 kpc of the Milky Way’s stellar disk, and estimate the projected 2D surface density map over the range R=10-20 kpc. In addition, we analyze a set of red clump giant candidates in the galactic plane obtained from 2MASS, GLIMPSE, and UKIDDS-GPS, confirm the previously identified break in the stellar volume density of red clump giants at a Galactocentric distance of 13 kpc and provide preliminary results on the density profile beyond the location of the stellar break.