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PG 1613+426: a new sdB pulsator

A. Bonanno·S. Catalano·A. Frasca·G. Mignemi·L. Paterno'
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Abstract

We report the detection of short period oscillations in the hot subdwarf B (sdB) star PG 1613+426 from time-series photometry carried out with the 91-cm Cassegrain telescope of the Catania Astrophysical Observatory. This star, which is brighter than the average of the presently known sdB pulsators, with B = 14.14 mag, has $T_{\rm eff}=34 400 {\rm K}$ and $\log g = 5.97$, its position is near the hot end of the sdB instability strip, and it is a pulsator with a well observed peak in the power spectrum at $144.18\pm 0.06 \rm s$. This star seems to be well suited for high precision measurements, which could detect a possible multi-mode pulsation behaviour

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A. Bonanno, S. Catalano, A. Frasca, G. Mignemi, L. Paterno'. 2002-12-06. PG 1613+426: a new sdB pulsator. https://doi.org/10.1051/0004-6361%3A20021664

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