Cyclotron Modeling Phase-Resolved Infrared Spectroscopy of Polars. II. EQ Ceti, AN Ursa Majoris, and VV Puppis
We present phase-resolved low-resolution infrared spectra of the polars EQ Cet, AN UMa, and VV Pup obtained with SPEX on the IRTF. In addition, we supplement our IRTF observations for VV Pup with optical data sets. The infrared spectra cover the wavelength range 0.8 μ m <= λ <= 2.4 μm and show cyclotron emission at all orbital phases for the three objects. We use a constant-lambda prescription to attempt to model the changing cyclotron features seen in the spectra. We model the EQ Cet data using two different approaches, yielding final parameters of Bsimeq 34.0 MG, kTsimeq 3.5 keV, and log Λ simeq 4.1. For AN UMa we find orbitally averaged models of B = 32.1 MG, kT = 5.0 keV, and log Λ simeq 4.3. We modeled phase-resolved spectra for VV Pup at four different epochs. We find the following range in parameters: 30.0 MG <= B<= 31.9 MG, 4.0 keV <= kT <= 15.0 keV, and 3.7 <= log Λ <= 6.5. Finally, we find that in B-kT space, the four epochs are well separated based on the visual brightness of the system at the time of observation.