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FUSE Spectroscopy of the Transitional Magnetic Cataclysmic Variable V405 Aurigae

David K. Sing·Steve B. Howell·Paula Szkody·France A. Cordova
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Abstract

We present Far Ultraviolet Spectroscopic Explorer observations of the magnetic cataclysmic variable V405 Aurigae. Together with four other DQ Her type binaries, V405 Aur forms a small subclass of intermediate polars which are likely to evolve into low magnetic field strength polars, similar to AM Her. Our co-added FUSE spectrum exhibits broad O VI and C III emission-lines as well as a narrow O VI emission-line component which likely forms near the white dwarf surface. The O VI 1032/1038 narrow emission line flux ratio is near 2.0 throughout the orbit, indicative of its formation in an optically thin gas. Radial velocity measurements of the narrow O VI emission-lines restrict any orbital modulation to a very low amplitude (Kwd = 2.5+/- 0.5 km/s) indicating, along with other single peaked broad disk emission lines in the UV and optical, that the binary system is at low inclination.

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David K. Sing, Steve B. Howell, Paula Szkody, France A. Cordova. 2004-09-29. FUSE Spectroscopy of the Transitional Magnetic Cataclysmic Variable V405 Aurigae. https://arxiv.org/abs/astro-ph/0409732

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