PG 1613 + 426 : a new sdB pulsator ⋆
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چکیده
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 eff = 34 400 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 ± 0.06 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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تاریخ انتشار 2008