Orbital Period of the Dwarf Nova RXS J053234.9+624755
  We report spectroscopy of the newly discovered SU Ursae Majoris dwarf nova identified with the x-ray source RXS J053234.9+624755. Radial velocities of the H-alpha emission line in the quiescent state give an orbital period of 0.05620(4) d (80.93 min), which is among the shortest for SU UMa stars with determined periods. We also report UBVI magnitudes of the quiescent dwarf nova and surrounding stars. Using a previous measurement of the superhump period, we find the fractional superhump excess epsilon to be 0.016(4), which is not atypical of dwarf novae in this period range. 
Ann B. Kapusta and John R. Thorstensen