X-ray emission from young stars in the massive star-forming region IRAS 20126+4104.
ANDERSON C.N., HOFNER P., SHEPHERD D. and CREECH-EAKMAN M.
Abstract (from CDS):
We present a 40 ks Chandra observation of the IRAS 20126+4104 core region. In the inner 6'' two X-ray sources were detected, which are coincident with the radio jet source I20S and the variable radio source I20Var. No X-ray emission was detected from the nearby massive protostar I20N. The spectra of both detected sources are hard and highly absorbed, with no emission below 3 keV. For I20S, the measured 0.5-8 keV count rate was 4.3 counts/ks. The X-ray spectrum was fitted with an absorbed 1T APEC model with an energy of kT =10 keV and an absorbing column of NH= 1.2x1023/cm2. An unabsorbed X-ray luminosity of about 1.4x1032 erg/s was estimated. The spectrum shows broad line emission between 6.4 and 6.7 keV, indicative of emission from both neutral and highly ionized iron. The X-ray light curve indicates that I20S is marginally variable; however, no flare emission was observed. The variable radio source I20Var was detected with a count rate of 0.9 counts/ks but there was no evidence of X-ray variability. The best-fit spectral model is a 1T APEC model with an absorbing hydrogen column of NH= 1.1x1023/cm2 and a plasma energy of kT = 6.0 keV. The unabsorbed X-ray luminosity is about 3x1031 erg/s.