Probing the Helium Enrichment of the Galactic Bulge with the Red Giant Branch Bump (David Nataf, The Ohio State University)

I discuss ongoing measurements of the red giant branch bump in globular clusters and the Galactic bulge, and how these measurements can be combined with stellar models to yield a unique probe of the age-metallicity-helium relationship. Using the OGLE-III bulge photometric survey, we find that the bulge RGBB may indicate a much higher level of helum enrichment than that observed in globular clusters, closer to Y~0.35 than Y~0.27 for stars at solar metallicity.