Infrared spectroscopy of cataclysmic variables -- II. Intermediate polars

We present infrared (0.97–2.45 μm) spectra of the intermediate polars PQ Gem (RE 0751 + 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 and 5100 K, respectively, or by power laws of the form fv ∝ v0.6,0.9, 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 field strengths; any cyclotron emission present must contribute less than ∼ 3 per cent of the infrared continuum flux.