Photometric amplitudes and phases of nonradial oscillation in rotating stars
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TLDR
In this paper, the effects of rotational mode coupling on photometric parameters of stellar oscillations are studied, where the authors show that at moderate rotation rates, a strong coupling between modes of spherical harmonic degree, differing by 2 and of the sameazimuthal order, m, takes place if the frequencies are close.Abstract:
Effects of rotational mode coupling on photometric parameters of stellar oscillations are studied. At moderate rotation rates, a strong coupling between modes of spherical harmonic degree, , differing by 2 and of the sameazimuthal order, m, takes place if the frequencies are close. This is a common situation amongst main sequence pulsators. Numerical results for a sequence of β Cephei star models are reported for the two- and three-mode couplings. One consequence of mode coupling is that modes of higher degree should be considered in photometric mode identification. Modes with nominal degree > 2 acquire substantial f ≤ 2 components and therefore are more likely to reach detectable amplitudes. Coupled mode positions in the amplitude ratio - phase difference diagrams, based on multicolour photometry, become both aspect- and m-dependent. Examples of the mode path in the diagram with varying aspect are given. The diagrams remain a useful tool for mode identification in rotating stars but the tool must be used with care.read more
Citations
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Asteroseismic measurement of slow, nearly uniform surface-to-core rotation in the main-sequence F star KIC 9244992
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Acoustic oscillations in rapidly rotating polytropic stars I. Effects of the centrifugal distortion
TL;DR: In this article, a non-perturbative method to compute accurate oscillation modes in rapidly rotating stars is presented, where the effect of the centrifugal force is fully taken into account while the Coriolis force is neglected.
References
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Delta Scuti and Related Stars
TL;DR: An extensive review of the current status of our knowledge of the stars in the lower instability strip is given in this paper, with particular attention given to the following areas: the confusion concerning naming and the implied astrophysical properties (often erroneous), single and multiple periods, the effect of rotation and metallicism on pulsation, the nature of the so-called dwarf cepheids, and pulsation in Ap stars.
Journal ArticleDOI
Delta scuti and related stars.
TL;DR: An extensive review of the current status of our knowledge of the stars in the lower instability strip is given in this paper, with particular attention given to the following areas: the confusion concerning naming and the implied astrophysical properties (often erroneous), single and multiple periods, the effect of rotation and metallicism on pulsation, the nature of the so-called dwarf cepheids, and pulsation in Ap stars.
Journal ArticleDOI
Effects of Differential Rotation on Stellar Oscillations: A Second-Order Theory
TL;DR: In this paper, a complete formalism, valid through second order in differential rotation, is developed and applied to calculate the frequencies of stellar oscillations, and the second-order effects are dominated by distortion for l < 500.
Journal ArticleDOI
Contributing factors to flux changes in nonradial stellar pulsations
TL;DR: In this article, a linearized analytic representation of observed flux changes due to nonradial pulsations is examined under conditions applicable to a variety of pulsating star types, and Histograms are presented as a function of l, documenting the relative importance of local temperature, geometry, pressure, and limb-darkening variations.
Journal ArticleDOI
Mode identification and asteroseismology of δ Scuti stars
L. A. Balona,E. A. Evers +1 more
TL;DR: In this paper, the use of multicolour photometry for mode identification in pulsating stars is discussed and a new, statistically based, algorithm for finding the best estimate of the spherical harmonic degree, and a confidence level from which the uniqueness can be ascertained.