Searching for the magnetised Tidal Dwarf Galaxies in Hickson Compact
  Groups: HCG 26, 91, and 96
  In this work, archive 1.4 and 4.86 GHz radio continuum data from the VLA were
re-reduced and, together with the 1.4 GHz maps from the NVSS, investigated for
the presence of a detectable, non-thermal continuum radio emission that could
be associated with the TDG candidates in HCG 26, 91, and 96. Radio emission
highly coincident with the optical and $\rm H_{\alpha}$ emission maxima of the
TDG candidate HCG 91i (estimated physical separation of less than 150 pc) was
revealed. Should this emission be intrinsic to this object, it would imply the
presence of a magnetic field as strong as 11--16 $\mu$G -- comparable to that
found in the most radio-luminous, star-forming dwarf galaxies of non-tidal
origin. However, the star formation rate derived for this object using the
radio flux is about two orders of magnitude higher, than the one estimated from
the $\rm H_{\alpha}$ data. Analysis of the auxiliary radio, ultraviolet and
infrared data suggests that either the radio emission originates in a
background object with an aged synchrotron spectrum (possibly a GHz-peaked
source), or the $\rm SFR_{H_{\alpha}}$ estimate is lower due to the fact that
it traces the most recent star formation, while most of the detected radio
emission originated when what is known as HCG 91i was still a part of its
parent galaxy. The latter scenario is supported by a very large stellar mass
derived from 3.6 and 4.5 $\mu$m data, implying high star formation in the past.
