1RXS J062518.2+733433: A new intermediate polar

¹ Department of Physics and Astronomy, University of Southampton, Southampton SO17 1BJ, UK
² Hamburger Sternwarte, Universität Hamburg, Gojenbergsweg 112, 21029 Hamburg, Germany

Corresponding author: S. Araujo-Betancor, sab@astro.soton.ac.uk

Received: 1 April 2003
Accepted: 30 April 2003

Abstract

We report the identification of the cataclysmic variable 1RXS J062518.2+733433 as an intermediate polar. The orbital period of the system is determined to be  min from the radial velocity variation of , measured in an extensive set of time-resolved spectra. Differential optical photometry obtained over a base line of three weeks reveals the presence of coherent variability with a period of  min, which we suggest to be the white dwarf spin period. The power spectrum of our photometry also contains a strong signal near the spectroscopically-determined orbital period. The emission lines in 1RXS J062518.2+733433 display a complex multicomponent structure. In the trailed spectrogram of He I λ 6678 we detect a narrow component with a radial velocity semi-amplitude of 140 kms, consistent with a possible origin on the irradiated face of the secondary. The absence of eclipses gives an upper limit on the binary inclination of .