The infrared K-band identification of the DSO/G2 source from VLT and Keck data

A fast moving infrared excess source (G2) which is widely interpreted as a core-less gas and dust cloud approaches Sagittarius A* (Sgr A*) on a presumably elliptical orbit. VLT K-s-band and Keck K'-band data result in clear continuum identifications and proper motions of this similar to 19(m) Dusty S-cluster Object (DSO). In 2002-2007 it is confused with the star S63, but free of confusion again since 2007. Its near-infrared (NIR) colors and a comparison to other sources in the field speak in favor of the DSO being an IR excess star with photospheric continuum emission at 2 microns than a core-less gas and dust cloud. We also find very compact L'-band emission (<0.1 ") contrasted by the reported extended (0.03 " up to similar to 2 " for the tail) Br gamma emission. The presence of a star will change the expected accretion phenomena, since a stellar Roche lobe may retain a fraction of the material during and after the peri-bothron passage.