Infrared Spectroscopy of Cataclysmic Variables -ii. Intermediate Polars
نویسنده
چکیده
We present infrared (0.97{2.45 micron) spectra of the intermediate polars PQ Gem (RE0751+14), BG CMi and EX Hya. The spectra show strong Paschen, Brackett and He I emission lines from the accretion disc/stream. The infrared continua of PQ Gem and BG CMi can be represented by blackbodies of temperatures 4500 K and 5100 K, respectively, or by power-laws of the form f / 0:6;0:9 , respectively, and show no evidence of secondary star features. The continuum of EX Hya is dominated by water bands from the red-dwarf secondary star, which has a spectral type of M3. Despite showing circular polarization, PQ Gem and BG CMi show no evidence for cyclotron humps and hence we are unable to measure their magnetic eld strengths; any cyclo-tron emission present must contribute less than 3% of the infrared continuum ux.
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