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تسجيل مستخدم جديدOn application of multi-colour photometry of $delta$ Scuti stars
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In $delta$ 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 $delta$ 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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In Delta Scuti star models, the calculated amplitude ratios and phase differences for multi-colour photometry exhibit a strong dependence on convection. These observables are tools for determination of the spherical harmonic degree of the excited mod
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