X-RAY AND RADIO OBSERVATIONS OF THE MASSIVE STAR-FORMING REGION IRAS 20126+4104

Abstract

We present results of Chandra ACIS-I and Karl G. Jansky Very Large Array (VLA) 6 cm continuum observations of the IRAS 20126+4104 massive star forming region. We detect 150 X-ray sources within the 17 arcmin x 17 arcmin ACIS-I field, and a total of 13 radio sources within the 9'.2 primary beam at 4.9 GHz. Among these are the first 6 cm detections of the central sources reported by Hofner et al. (2007), namely I20N1, I20S, and I20var. A new variable radio sources is also reported. Searching the 2MASS archive we identified 88 NIR counterparts to the X-ray sources. Only 4 of the X-ray sources had 6 cm counterparts. Based on an NIR color-color analysis, and on the Besancon simulation of Galactic stellar populations (Robin et al. 2003), we estimate that about 90 X-ray sources are associated with this massive star forming region. We detect an increasing surface density of X-ray sources toward the massive protostar and infer the presence of a cluster of at least 46 YSOs within a distance of 1.2 pc from the massive protostar.