A search for non-thermal radio emission from jets of massive young
  stellar objects
  Massive young stellar objects (MYSOs) have recently been shown to drive jets
whose particles can interact with either the magnetic fields of the jet or
ambient medium to emit non-thermal radiation. We report a search for
non-thermal radio emission from a sample of 15 MYSOs to establish the
prevalence of the emission in the objects. We used their spectra across the L-,
C- and Q-bands along with spectral index maps to characterise their emission.
We find that about 50% of the sources show evidence for non-thermal emission
with 40% showing clear non-thermal lobes, especially sources of higher
bolometric luminosity. The common or IRAS names of the sources that manifest
non-thermal lobes are; V645Cyg, IRAS 22134+5834, NGC 7538 IRS 9, IRAS
23262+640, AFGL 402d and AFGL 490. All the central cores of the sources are
thermal with corresponding mass-loss rates that lie in the range 3X10^{-7} to
7X10^{-6} solar masses per year. Given the presence of non-thermal lobes in
some of the sources and the evidence of non-thermal emission from some spectral
index maps, it seems that magnetic fields play a significant role in the jets
of massive protostars. Also noted is that some of the sources show evidence of
binarity and variability.
