Newly discovered cataclysmic variables from the INT/WFC photometric Hα 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 HSurvey 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 IPHAS J051814.34+294113.2, time-resolved optical spectroscopy has been obtained and radial-velocity measurements of the Hemission-line have been used to estimate their orbital periods. A third CV candidate (IPHAS J062746.41+ 014811.3) was ob- served photometrically and found to be eclipsing. All three systems have orbital pe- riods above the CV period-gap of 2-3 h. We also highlight one other system, IPHAS J025827.88+635234.9, whose spectrum distinguishes it as a likely high luminosity ob- ject with unusual C and N abundances.