The Discovery of an Embedded Cluster of High-Mass Stars near SGR 1900+14

Abstract

Deep I-band imaging to I approximately 26.5 of the soft gamma-ray repeater SGR 1900+14 region has revealed a compact cluster of massive stars located only a few arcseconds from the fading radio source thought to be the location of the soft gamma-ray repeater (SGR). This cluster was previously hidden in the glare of the pair of M5 supergiant stars (whose light was removed by point-spread function subtraction) proposed by Vrba et al. as likely associated with SGR 1900+14. The cluster has at least 13 members within a cluster radius of approximately 0.6 pc based on an estimated distance of 12-15 kpc. It is remarkably similar to a cluster found associated with SGR 1806-20. That similar clusters have now been found at or near the positions of the two best studied SGRs suggests that young neutron stars, which are thought to be responsible for the SGR phenomenon, have their origins in proximate compact clusters of massive stars.