A new class of pulsating star, the EC14026 stars, has been discovered. These stars are pulsating hot subdwarfs with log g ~ 6.0 and Teff ~ 35000 K. The oscillations are multiperiodic with periods in the range 120s < P < 500s and amplitudes typically less than 1 percent. In a photometric survey to discover new members of this class so far ten pulsators have been identified. The observed pulsation characteristics of these pulsators will be described and the modes of oscillation and excitation mechanism discussed. Spectrograms of the pulsators reveal that most of the stars are composite in nature comprising a hot subdwarf and a cooler main sequence F/G type star. The binary orbit should be derivable either from the radial velocity change (shorter orbital periods) or the light time effect (longer orbital periods). These stars are amongst the most compact oscillators known. They form an excellent laboratory for the asteroseismological understanding of hot subdwarfs, once the modes of oscillation are identified, and for measuring the rate of evolution of subdwarfs.
A Half Century of Stellar Pulsation Interpretation
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