The Supersonic Project: Shining Light on SIGOs - a New Formation Channel
  for Globular Clusters
  Supersonically induced gas objects (SIGOs) with little to no dark matter
component are predicted to exist in patches of the Universe with non-negligible
relative velocity between baryons and the dark matter at the time of
recombination. Using {\sc arepo} hydrodynamic simulations we find that the gas
densities inside these objects are high enough to allow stars to form. An
estimate of the luminosity of the first star clusters formed within these SIGOs
suggests that they may be observed at high redshift using future HST and JWST
observations. Furthermore, our simulations indicate that SIGOs lie in a
distinct place in the luminosity-radius parameter space, which can be used
observationally to distinguish SIGOs from dark-matter hosting gas systems.
Finally, as a proof-of-concept, we model star formation before reionization and
evolve these systems to current times. We find that SIGOs occupy a similar part
of the magnitude-radius parameter space as globular clusters. These results
suggest that SIGOs may be linked with present-day metal-poor local globular
clusters. Since the relative velocity between the baryons and dark matter is
coherent over a few Mpc scales, we predict that if this is the dominant
mechanism for the formation of globular clusters, their abundance should vary
significantly over these scales.
