First evidence for solar-like oscillations in a δ Scuti star

V. Antoci, G. Handler, T. L. Campante, A. O. Thygesen, A. Moya Bedón, T. Kallinger, D. Stello, A. Grigahcène, H. Kjeldsen

Abstract.
Theoretical predictions suggest that solar-like oscillations should exist in delta Scuti stars. Up to now no such oscillations have been observed, seriously questioning our understanding of the physics occurring in the outer layers of these stars. Using ultra-precise data from the Kepler mission, we show here the first evidence of these predicted pulsations. Our interpretation is supported by the striking similarities between the observed signal at high frequencies and the properties of stochastically excited pulsation, i.e. 1) overtones of high radial order with a rough equidistant spacing, 2) evidence for short mode lifetimes, 3) correct estimate for the frequency of maximum power for the observed large separation, 4) amplitudes comparable to predictions, and 5) statistical evidence for the stochastic nature of the signal.

20th Stellar Pulsation Conference Series
Granada, Spain
September 2011

Type: Oral comunication