The effect of rotation, up to second order, on the oscillation frequencies of some delta-scuti stars

Doğan, Gülnur
In this work, the effect of rotation on the oscillation frequencies of some radially and nonradially oscillating Delta-Scuti stars have been explored. Rotation has been considered as a perturbation and treated up to the second order. Series of evolutionary models have been calculated for the oscillating stars in question and compared with the observational parameters. Three stars are considered: V350 Peg with no rotation, CC And with a rotational velocity Vsini=20 km/s, and BS Tuc with Vsini=130 km/s. We find that splitting in the oscillation frequencies are conspicuous especially in fast rotating stars, with a considerable contribution from the related terms due to second order effect.


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Citation Formats
G. Doğan, “The effect of rotation, up to second order, on the oscillation frequencies of some delta-scuti stars,” M.S. - Master of Science, Middle East Technical University, 2007.