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A white dwarf with a low magnetic field in the IP RXJ0028.8+5917/V709Cas

J. M. Bonnet-Bidaud·M. Mouchet·D. de Martino·G. Matt·C. Motch
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Abstract

We report the first detailed spectroscopic observations of the recently identified intermediate polar RXJ0028.8+5917/V709 Cas. We discovered that the system shows significant EW ~ (2-4)A broad absorptions, affecting the Balmer lines from Hdelta to Hbeta. These broad absorptions are interpreted as the contribution of an underlying DA logg=8 white dwarf at a temperature of ~ 23 000 K, contributing ~ 17 % (at 4500 A) to the overall flux. This is the first direct detection of a white dwarf in an intermediate polar system. The absence of significant Zeeman splitting indicates a magnetic field lower than 10 MG, confirming that, at least in some cases, intermediate polars have weaker fields than polars.

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J. M. Bonnet-Bidaud, M. Mouchet, D. de Martino, G. Matt, C. Motch. 2001-10-01. A white dwarf with a low magnetic field in the IP RXJ0028.8+5917/V709Cas. https://arxiv.org/abs/astro-ph/0110036

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