Opportunities for probing $U(1)_{T3R}$ with light mediators
  We consider strategies for using new datasets to probe scenarios in which
light right-handed SM fermions couple to a new gauge group, $U(1)_{T3R}$. This
scenario provides a natural explanation for the light flavor sector scale, and
a motivation for sub-GeV dark matter. There is parameter space which is
currently allowed, but we find that much of it can be probed with future
experiments. In particular, cosmological and astrophysical observations,
neutrino experiments and experiments which search for displaced visible decay
or invisible decay can all play a role. Still, there is a small region of
parameter space which even these upcoming experiments will not be able to
probe. This model can explain the observed 2.4-3$\sigma$ excess of events at
the COHERENT experiment in the parameter space allowed by current laboratory
experiments, but the ongoing/upcoming laboratory experiments will decisively
probe this possibility.
