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The Radial Velocity and Mass of the White Dwarf of EX Hydrae Measured with Chandra

R. Hoogerwerf·N. S. Brickhouse·C. W. Mauche
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Abstract

We present the first detection of orbital motion in the cataclysmic variable EX Hydrae based on X-ray data from the Chandra X-ray Observatory. The large collecting area of the telescope and the high resolution of the HETG spectrometers allow for an unprecedented velocity accuracy of ~15 km/s in the X-ray wavelength regime. We find an emission line velocity amplitude of 58.2+-3.7 km/s and infer a white dwarf mass of 0.49+-0.13 M_sun, in good agreement with previous studies using optical, ultraviolet, and far ultraviolet data.

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R. Hoogerwerf, N. S. Brickhouse, C. W. Mauche. 2004-03-29. The Radial Velocity and Mass of the White Dwarf of EX Hydrae Measured with Chandra. https://doi.org/10.1086/421389

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