2MASS Studies of Differential Reddening across Three Massive Globular Clusters

Abstract

J-, H-, and Ks-band data from the Two Micron All Sky Survey (2MASS) are used to study the effects of differential reddening across the three massive Galactic globular clusters ω Centauri, NGC 6388, and NGC 6441. Evidence is found that variable extinction may produce false detections of tidal tails around ω Centauri. We also investigate what appears to be relatively strong differential reddening toward NGC 6388 and NGC 6441 and find that differential extinction may be exaggerating the need for a metallicity spread to explain the width of the red giant branches for these two clusters. Finally, we consider the implications of these results for the connection between unusual, multipopulation globular clusters and the cores of dwarf spheroidal galaxies (dSph).