Newly discovered cataclysmic variables from the INT/WFC photometric Halpha survey of the northern Galactic plane

Abstract

We report the discovery of 11 new cataclysmic variable (CV) candidates by the Isaac Newton Telescope (INT) Photometric Halpha Survey of the northern Galactic plane (IPHAS). Three of the systems have been the subject of further follow-up observations. For the CV candidates IPHAS J013031.90+622132.4 and J051814.34+294113.2, time-resolved optical spectroscopy has been obtained and radial-velocity measurements of the Halpha emission line have been used to estimate their orbital periods. A third CV candidate (IPHAS J062746.41+014811.3) was observed photometrically and found to be eclipsing. All three systems have orbital periods above the CV period gap of 2-3h. We also highlight an other system, IPHAS J025827.88+635234.9, whose spectrum distinguishes it as a likely high-luminosity object with unusual C and N abundances.