Infrared spectroscopy of cataclysmic variables - II. Intermediate polars
Abstract
We present infrared (0.97-2.45mum) spectra of the intermediate polars PQGem (RE 0751+14), BGCMi and EXHya. The spectra show strong Paschen, Brackett and He i emission lines from the accretion disc/stream. The infrared continua of PQGem and BGCMi can be represented by blackbodies of temperatures 4500 and 5100K, respectively, or by power laws of the form f_nu~nu^0.6, 0.9, respectively, and show no evidence of secondary star features. The continuum of EXHya is dominated by water bands from the red dwarf secondary star, which has a spectral type of ~M3. Despite showing circular polarization, PQGem and BGCMi show no evidence for cyclotron humps, and hence we are unable to measure their magnetic field strengths; any cyclotron emission present must contribute less than ~3 per cent of the infrared continuum flux.
- Publication:
-
Monthly Notices of the Royal Astronomical Society
- Pub Date:
- February 1997
- DOI:
- 10.1093/mnras/285.1.95
- arXiv:
- arXiv:astro-ph/9609047
- Bibcode:
- 1997MNRAS.285...95D
- Keywords:
-
- BINARIES: CLOSE;
- STARS: INDIVIDUAL: PQGEM;
- STARS: INDIVIDUAL: BGCMI;
- STARS: INDIVIDUAL: EXHYA;
- NOVAE;
- CATACLYSMIC VARIABLES;
- INFRARED: STARS.;
- Astrophysics
- E-Print:
- 7 pages, 2 figures