Description
High resolution and high signal to noise ratio spectroscopic observations of the classical {beta} Cephei star {gamma} Peg were obtained between 1991 and 2005. The analysis of these data combined with previously published results shows that {gamma} Peg is a spectroscopic binary with an orbital period of 370.5d. We discovered three new frequencies in addition to the well-known 6.5897d^-1^ (0.15175d) one. That at 6.01d^-1^ is a typical Cephei frequency. The two others at 0.68 and 0.87d^-1^ are similar to the high degree g-mode frequencies found in SPB stars. Thus, {gamma} Peg is a hybrid {beta} Cephei-SPB star. Its position in the HR diagram is compatible with such a status. In addition, a small increase of the main period has been detected between the 1995 and 2005 observations.
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