Dynamical modelling of disc vertical structure in superthin galaxy `UGC
  7321' in braneworld gravity: An MCMC study
  Low surface brightness (LSBs) superthins constitute classic examples of very
late-type galaxies, with their disc dynamics strongly regulated by their dark
matter halos. In this work we consider a gravitational origin of dark matter in
the brane world scenario, where the higher dimensional Weyl stress term
projected onto the 3-brane acts as the source of dark matter. In the context of
the braneworld model, this dark matter is referred to as the \emph{`dark
mass'}.This model has been successful in reproducing the rotation curves of
several low surface brightness and high surface brightness galaxies. Therefore
it is interesting to study the prospect of this model in explaining the
vertical structure of galaxies which has not been explored in the literature so
far. Using our 2-component model of gravitationally-coupled stars and gas in
the external force field of this \emph{dark mass}, we fit the observed scale
heights of stellar and atomic hydrogen (HI) gas of superthin galaxy `UGC7321'
using the Markov Chain Monte Carlo approach. We find that the observed
scaleheights of `UGC7321' can be successfully modelled in the context of the
braneworld scenario. In addition, the model predicted rotation curve also
matches the observed one. The implications on the model parameters are
discussed.
