Characterizing the radio continuum nature of sources in the massive
  star-forming region W75N (B)
  The massive star-forming region W75N~(B) is thought to host a cluster of
massive protostars (VLA~1, VLA~2, and VLA~3) undergoing different evolutionary
stages. In this work, we present radio continuum data with the highest
sensitivity and angular resolution obtained to date in this region, using the
VLA-A and covering a wide range of frequencies (4-48~GHz), which allowed us to
study the morphology and the nature of the emission of the different radio
continuum sources. We also performed complementary studies with multi-epoch VLA
data and ALMA archive data at 1.3 mm wavelength. We find that VLA~1 is driving
a thermal radio jet at scales of $\approx$0.1 arcsec ($\approx$130 au), but
also shows signs of an incipient hyper-compact HII region at scales of
$\lesssim$ 1 arcsec ($\lesssim$ 1300~au). VLA~3 is also driving a thermal radio
jet at scales of a few tenths of arcsec (few hundred of au). We conclude that
this jet is shock-exciting the radio continuum sources Bc and VLA~4 (obscured
HH objects), which show proper motions moving outward from VLA~3 at velocities
of $\approx$112--118~km/s. We have also detected three new weak radio continuum
sources, two of them associated with millimeter continuum cores observed with
ALMA, suggesting that these two sources are also embedded YSOs in this massive
star-forming region.
