A New Method for Isolating M31 Red Giant Stars: The Discovery of Stars out to a Radial Distance of 165 Kiloparsecs

Karoline M. Gilbert, Puragra Guhathakurta, Jasonjot S. Kalirai +8

We present a method for isolating a clean sample of red giant stars in the outerregions of the Andromeda spiral galaxy (M31) from an ongoing spectroscopic survey using the DEIMOS i…