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Time-resolved spectroscopy and spectrophotometry of the pulsating sdB star PG 1605+072

S. J. O'Toole·T. R. Bedding·H. Kjeldsen·M. A. S. G. Joergensen
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Abstract

We present the latest results from our analysis of time resolved spectroscopy of PG 1605+072, a high amplitude pulsating sdB star. The star is believed to have evolved off the extreme horizontal branch, and it is uncertain whether it pulsates in p- or g-modes. Previous studies of PG 1605+072 have found amplitude variation and/or very closely spaced frequencies. We compare our velocity measurements with new simultaneous spectrophotometric measurements and analyse phase differences for the 8 frequencies found in velocity. Phase differences between velocity, spectrophotometry and equivalent width are discussed.

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S. J. O'Toole, T. R. Bedding, H. Kjeldsen, M. A. S. G. Joergensen. 2002-10-17. Time-resolved spectroscopy and spectrophotometry of the pulsating sdB star PG 1605+072. https://arxiv.org/abs/astro-ph/0210395

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