Tracing the Sgr Stream with 2MASS. Detection of Stream stars around Outer Halo Globular Clusters

TL;DR

This study uses 2MASS infrared data to identify stars from the Sagittarius stream around certain globular clusters, providing evidence of their past association with the Sgr dwarf galaxy.

Contribution

It demonstrates a method to detect Sgr stream stars around globular clusters using infrared CMDs, confirming cluster associations with the stream.

Findings

Significant detection of Sgr stream stars around Pal 12 and NGC 4147.

Evidence supporting these clusters' past membership in the Sgr dSph galaxy.

Validation of infrared CMDs as effective tools for stream detection.

Abstract

We use infrared Color Magnitude Diagrams from the 2-Micron All-Sky Survey (2MASS) to search for stars belonging to the tidal stream of the Sagittarius dwarf spheroidal galaxy (Sgr dSph) around selected Galactic globular clusters. Statistically significant detections are presented for the cases of Pal 12 and NGC 4147, strongly supporting the idea that these clusters are associated with the Sgr Stream and that they were previous members of the Sgr dSph galaxy.