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arXiv · 1103.1600

RAT J0455+1305: A rare hybrid pulsating subdwarf B star

A. S. Baran·J. T. Gilker·L. Fox-Machado·M. D. Reed·S. D. Kawaler
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Abstract

We present results on the second-faintest pulsating subdwarf B (sdB) star known, RAT J0455+1305, derived from photometric data obtained in 2009. It shows both short and long periods oscillations, theoretically assigned as pressure and gravity modes. We identify six short-period frequencies (with one being a combination) and six long-period frequencies. This star is the fourth hybrid sdB star discovered so far which makes it of special interest as each type of mode probes a different part of the star. This star is similar to the sdB hybrid pulsator Balloon 090100001 in that it exhibits short-period mode groupings, which can be used to identify pulsation parameters and constrain theoretical models.

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A. S. Baran, J. T. Gilker, L. Fox-Machado, M. D. Reed, S. D. Kawaler. 2011-03-08. RAT J0455+1305: A rare hybrid pulsating subdwarf B star. https://doi.org/10.1111/j.1365-2966.2010.17718.x

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