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Time-series Spectroscopy of EC14026 Stars: Preliminary Results

Simon J. O'Toole·Teresa C. Teixeira·Timothy R. Bedding·Hans Kjeldsen
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Abstract

We have obtained time-series spectra for the pulsating hot subdwarf (sdB) PG1605+072. Previous time-series photometry of this star has shown maximum amplitude variations of about 0.1 mag and at least 50 periods. The pulsator has the largest amplitude and longest periods of all the pulsating sdBs (or EC14026 stars) discovered so far, and appears to be unusual in its class. Preliminary results of a search for velocity variations are presented here. With these variations, along with equivalent width measurements, oscillation mode identification should be possible.

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Simon J. O'Toole, Teresa C. Teixeira, Timothy R. Bedding, Hans Kjeldsen. 1999-11-05. Time-series Spectroscopy of EC14026 Stars: Preliminary Results. https://arxiv.org/abs/astro-ph/9911074

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