Photometric sample of 2.6million red clump stars

However, it is difficult to cleanly select red clumps stars because they can have the same Teff and logg as red giant branch stars. Recently, it was shown that the asteroseismic parameters, {DELTA}P and {DELTA}{nu}, which are used to accurately select red clump stars, can be derived from spectra using the change in the surface carbon to nitrogen ratio ([C/N]) caused by mixing during the red giant branch.

This change in [C/N] can also impact the spectral energy distribution. In this study, we predict the {DELTA}P, {DELTA}{nu}, Teff and logg using 2MASS, AllWISE, Gaia, and Pan-STARRS data in order to select a clean sample of red clump stars. We achieve a contamination rate of ~20%, equivalent to what is achieved when selecting from Teff and logg derived from low resolution spectra.