Photometric and spectroscopic observations of the optical counterpart of H2215-086

Photometric and spectroscopic observations of the optical counterpart of the X-ray source H2215-086 are reported. The periodicity near 21 min is confirmed and the binary nature of the object established. It is suggested that this object, like V1223 Sgr, is remarkably similar to H2252-035. Two fundamental periodicities are associated with the star. It is suspected that the 21-min optical pulsation is due to hard radiation from magnetic poles of a compact star, reprocessed by material which is at rest in a frame corotating with the binary. Based on the broad emission lines which primarily originate in the reprocessing region, it appears that the most likely location for this region is in the raised rim of the accretion disk near the hot spot. The spectrum and the ratio of X-ray to optical luminosity argue that the object is a white dwarf.