Infrared photometry of metal rich galactic globular clusters

Infrared photometry is presented for the giant branches of five galactic globular clusters, including three very metal rich ones located near the galactic center. New visual photometry was required for three of these objects. The metallicities of these clusters as inferred from the dereddened colors of their giant branches are in reasonable agreement with those inferred by spectroscopy of the integrated light of these systems. The spread in color seen along the giant branches of the most highly reddened of these globular clusters is shown to be consistent with patchy interstellar reddening. Abundance variations within a cluster are not required to explain the observations. The range of metallicity is confined to less than 0.2 dex in NGC 5927, and to 0.1 dex in NGC 7099. The spread in V—K color is a strong constraint on abundance variations within a globular cluster