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A 150MG magnetic white dwarf in the cataclysmic variable RX J1554.2+2721

B. T. Gaensicke·S. Jordan·K. Beuermann·D. de Martino·P. Szkody·T. Marsh·J. Thorstensen
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Abstract

We report the detection of Zeeman-split Lalpha absorption pi and sigma+ lines in the far-ultraviolet Hubble Space Telescope/Space Telescope Imaging Spectrograph spectrum of the magnetic cataclysmic variable RX J1554.2+2721. Fitting the STIS data with magnetic white dwarf model spectra, we derive a field strength of B~144MG and an effective temperature of 17000K<Teff<23000K. This measurement makes RX J1554.2+2721 only the third cataclysmic variable containing a white dwarf with a field exceeding 100MG. Similar to the other high-field polar AR UMa, RX J1554.2+2721 is often found in a state of feeble mass transfer, which suggests that a considerable number of high-field polars may still remain undiscovered.

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B. T. Gaensicke, S. Jordan, K. Beuermann, D. de Martino, P. Szkody, T. Marsh, J. Thorstensen. 2004-08-17. A 150MG magnetic white dwarf in the cataclysmic variable RX J1554.2+2721. https://doi.org/10.1086/425141

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