Dynamical Modelling Of Disc Vertical Structure In Superthin Galaxy 'Ugc 7321' In Braneworld Gravity: An Mcmc Study

Lowsurface brightness (LSBs) superthins constitute classic examples of very late-type galaxies, with their disc dynamics strongly regulated by their dark matter haloes. In this work, we consider a gravitational origin of dark matter in the braneworld scenario, where the higher dimensional Weyl stress term projected on to the three-brane acts as the source of dark matter. In the context of the braneworld model, this dark matter is referred to as the 'dark mass'. This model has been successful in reproducing the rotation curves of several LSB 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 two-component model of gravitationally coupled stars and gas in the external force field of this dark mass, we fit the observed scale heights of stellar and atomic hydrogen (H I) gas of superthin galaxy 'UGC7321' using the Markov Chain Monte Carlo approach. We find that the observed scale heights 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.