Program: GS-2010A-C-7

The presence of a large helium abundance inhomogeneity in the globular cluster Omega Centauri, signaled by a bifurcation of colors in the middle main sequence, can be tested directly. We propose a measure of the strength of the \ion{He}{1} 10830\AA\ absorption line in stars on the red giant branch of the cluster. Helium absorption occurs in metal-poor stars with $T_{eff} > 4500K$ both in the field and in the clusters, M4 and M13. PHOENIX spectra of a sample of red giants in Omega Cen can reveal the presence (or not) of a bimodal distribution of helium equivalent widths in a sample of red giants not subject to diffusion or abundance stratification.