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arXiv · 2506.17674

On accretion in the polar V379 Vir

M. V. Suslikov·A. I. Kolbin·N. V. Borisov
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Abstract

Based on optical and infrared survey data spanning $\approx 20$ years of observations, the long-term variability of the polar V379 Vir with a brown dwarf secondary has been studied. By modeling the spectral energy distribution, we constrain the white dwarf's mass to $M_1 = 0.61 \pm 0.05~M_{\odot}$ and its effective temperature to $T_{eff} = 10930 \pm 350~K$. Near-infrared photometry yields a donor radius of $R_2 = 0.095 \pm 0.018 R_{\odot}$ and temperature $T_{eff} = 1600 \pm 180 K$. Modeling of the cyclotron emission from the accretion spot, detected with the Spitzer infrared telescope, gives an accretion rate of $\dot{M} \approx 3 \times 10^{-13} M_{\odot}/yr$. This rate is consistent with polars in a low accretion state, but significantly higher than expected from wind-driven mass transfer.

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M. V. Suslikov, A. I. Kolbin, N. V. Borisov. 2025-06-21. On accretion in the polar V379 Vir. https://arxiv.org/abs/2506.17674

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