Abstract
We present phase-resolved low-resolution JHK and higher resolution K-band spectroscopy of the polar VV Pup. All observations were obtained when VV Pup was in a low-accretion state having a K magnitude near 15. The low-resolution observations reveal cyclotron emission in the J band during some phases, consistent with an origin near the active 30.5 MG pole on the white dwarf. The secondary in VV Pup appears to be a normal M7 V star, and we find that the H- and K-band fluxes are entirely due to this star at all orbital phases during the low-accretion state. We use our higher resolution Keck spectroscopy to produce the first K-band radial velocity curve for VV Pup. Our orbital solution yields K2 = 414 ± 27 km s-1 and leads to mass estimates of M1 = 0.73 ± 0.05 M⊙ and M2 = 0.10 ± 0.02 M⊙. We find that the mass accretion rates during the normal low states of the polars VV Pup, EF Eri, and EQ Cet are near 10-13 M⊙ yr-1. The fact that is not zero in low-state polars indicates active secondary stars in these binary systems, including the substellar donor star present in EF Eri.
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