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Rapid Oscillations in Cataclysmic Variables. XV. HT Camelopardalis (= RX J0757.0+6306)

Jonathan Kemp·Joseph Patterson·John Thorstensen·Robert Fried·David Skillman·Gary Billings
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Abstract

We present photometry and spectroscopy of HT Camelopardalis, a recently discovered X-ray-bright cataclysmic variable. The spectrum shows bright lines of H, He I, and He II, all moving with a period of 0.059712(1) d, which we interpret as the orbital period. The star's brightness varies with a strict period of 515.0592(2) s, and a mean full amplitude of 0.11 mag. These properties qualify it as a /bona fide/ DQ Herculis star (intermediate polar) -- in which the magnetism of the rapidly rotating white dwarf channels accretion flow to the surface. Normally at V=17.8, the star shows rare and very brief outbursts to V=12-13. We observed one in December 2001, and found that the 515 s pulse amplitude had increased by a factor of ~100 (in flux units). A transient orbital signal may also have appeared.

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Jonathan Kemp, Joseph Patterson, John Thorstensen, Robert Fried, David Skillman, Gary Billings. 2002-04-13. Rapid Oscillations in Cataclysmic Variables. XV. HT Camelopardalis (= RX J0757.0+6306). https://doi.org/10.1086/341686

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