The serendipituous discovery of a short-period eclipsing polar in 2XMMp

We report the serendipituous discovery of the new eclipsing polar 2XMMp J131223.4+173659. Its striking X-ray light curve attracted immediate interest when we were visually inspecting the source products of the 2XMMp catalogue. This light curve revealed its likely nature as a magnetic cataclysmic variable of AM Herculis (or polar) type with an orbital period of ~92 min, which was confirmed by follow-up optical spectroscopy and photometry. 2XMMp J131223.4+173659 probably has a one-pole accretion geometry. It joins the group of now nine objects that show no evidence of a soft component in their X-ray spectra despite being in a high accretion state, thus escaping ROSAT/EUVE detection. We discuss the likely accretion scenario, the system parameters, and the spectral energy distribution.