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Radial velocity variations of the pulsating subdwarf B star PG 1605+072

Vincent M. Woolf·C. Simon Jeffery·Donald L. Pollacco
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Abstract

We present an analysis of high-speed spectroscopy of the pulsating subdwarf B star PG 1605+072. Periodic radial motions are detected at frequencies similar to those reported for photometric variations in the star, with amplitudes of up to 6 km/s. Differences between relative strengths for given frequency peaks for our velocity data and previously measured photometry are probably a result of shifting of power between modes over time. Small differences in the detected frequencies may also indicate mode-shifting. We report the detection of line-shape variations using the moments of the cross correlation function profiles. It may be possible to use the moments to identify the star's pulsation modes.

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Vincent M. Woolf, C. Simon Jeffery, Donald L. Pollacco. 2001-11-12. Radial velocity variations of the pulsating subdwarf B star PG 1605+072. https://doi.org/10.1046/j.1365-8711.2002.04995.x

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