| Abstract : | Ultra diffuse galaxies (UDGs) constitute a class of galaxies with very low central stellar surface brightness yet relatively large disc size given their dynamical mass in the dwarf regime. These galaxies have been observed in all possible environments in the universe, the effect of their local habitat being reflected upon their structure and kinematics. UDGs in clusters are reportedly dark matter-rich as well as dark matter-less, devoid of atomic hydrogen gas due to ram-pressure stripping and star formation quenched as indicated by their red appearance. The physical mechanisms originating from the strong tidal field present in the cluster, e.g. tidal heating, tidal stripping, have dominant effects in the evolution of cluster UDGs. Several studies have shown that tidal heating or stripping can significantly alter the dynamics of dwarf galaxies infalling into the cluster thus transforming them into UDGs; though the effect of tidal torquing has not been studied much in the literature in this context. Moreover, the non-spherical shape of the cluster dark matter halo, as indicated by gravitational weak-lensing studies, may enhance the torquing effect which in turn may take over tidal heating or stripping in shaping UDGs. In this work, we investigate the effect of tidal torquing by a non-spherical cluster dark matter halo over other physical mechanisms ascribed to the cluster tidal field in the formation and evolution of UDGs employing N-body+hydrodynamical simulations.
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