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On application of multi-colour photometry of $δ$ Scuti stars

J. Daszy{ń}ska-Daszkiewicz·W. A. Dziembowski·A. A. Pamyatnykh
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Abstract

In $δ$ Scuti star models, the photometric amplitudes and phases exhibit a strong dependence on convection, which enters through the complex parameter, $f$, which describes the bolometric flux variation. We present a new method of extracting simultaneously $\ell$ and $f$ from multi-colour data and apply it to several $δ$ Scuti stars. The inferred values of $f$ are sufficiently accurate to yield an useful constraint on models of stellar convection. In addition, if the identified mode is radial, the multi-passband data may be used to refine global stellar parameters. Finally, the usage of radial velocity measurements to our method improves significantly determination of $\ell$ and $f$.

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J. Daszy{ń}ska-Daszkiewicz, W. A. Dziembowski, A. A. Pamyatnykh. 2003-09-11. On application of multi-colour photometry of $δ$ Scuti stars. https://arxiv.org/abs/astro-ph/0309319

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