Pfleiderer 2 : identification of a new globular cluster in the galaxy

Abstract

We provide evidence that indicates the star cluster Pfleiderer 2, which is projected in a rich field, as a newly identified Galactic globular cluster. Since it is located in a crowded field, core extraction and decontamination tools were applied to reveal the cluster sequences in B, V, and I color–magnitude diagrams (CMDs). The main CMD features of Pfleiderer 2 are a tilted red giant branch and a red horizontal branch, indicating a high metallicity around solar. The reddening is E(B − V ) = 1.01. The globular cluster is located at a distance of d = 16 ± 2 kpc from the Sun. The cluster is located 2.7 kpc above the Galactic plane and at a distance of RGC = 9.7 kpc from the Galactic center, which is unusual for a metal-rich globular cluster.