The infrared K-band identification of the DSO/G2 source from VLT and Keck data
Abstract
A fast moving infrared excess source (G2) which is widely interpreted as a core-less gas and dust cloud approaches Sagittarius A* (SgrA*) on a presumably elliptical orbit. VLT K_s-band and Keck K'-band data result in clear continuum identifications and proper motions of this about 19m 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 about 0.2'' for the tail) Brgamma 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.
Keywords
Cite
@article{arxiv.1311.2753,
title = {The infrared K-band identification of the DSO/G2 source from VLT and Keck data},
author = {Andreas Eckart and M. Horrobin and S. Britzen and M. Zamaninasab and K. Muzic and N. Sabha and B. Shahzamanian and S. Yazici and L. Moser and M. Garcia-Mari and M. Valencia-S. and A. Borkar and M. Bursa and G. Karssen and V. Karas and M. Zajacek and L. Bronfman and R. Finger and B. Jalali and M. Vitale and C. Rauch and D. Kunneriath and J. Moultaka and C. Straubmeier and Y. E. Rashed and K. Markakis and A. Zensus},
journal= {arXiv preprint arXiv:1311.2753},
year = {2015}
}
Comments
4 pages, 2 figures, Proc. of a Conf. on IAU Symposium No.303: The GC: Feeding and Feedback in a Normal Galactic Nucleus 2013 September 30 - October 4, Santa Fe New Mexico (USA)