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Related papers: Asymptotic analysis of high-frequency acoustic mod…

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Effects of rapid stellar rotation on acoustic oscillation modes are poorly understood. We study the dynamics of acoustic rays in rotating polytropic stars and show using quantum chaos concepts that the eigenfrequency spectrum is a…

Astrophysics · Physics 2009-06-23 F. Lignieres , B. Georgeot

Despite more and more observational data, stellar acoustic oscillation modes are not well understood as soon as rotation cannot be treated perturbatively. In a way similar to semiclassical theory in quantum physics, we use acoustic ray…

Solar and Stellar Astrophysics · Physics 2011-09-16 M. Pasek , B. Georgeot , F. Lignieres , D. R. Reese

We present an asymptotic theory that describes regular frequency spacings of pressure modes in rapidly rotating stars. We use an asymptotic method based on an approximate solution of the pressure wave equation constructed from a stable…

Solar and Stellar Astrophysics · Physics 2012-09-27 Michael Pasek , François Lignières , Bertrand Georgeot , Daniel R. Reese

Recent observations of rapidly rotating stars have revealed the presence of regular patterns in their pulsation spectra. This has raised the question as to their physical origin, and in particular, whether they can be explained by an…

Solar and Stellar Astrophysics · Physics 2015-06-17 Daniel R. Reese , Francisco Espinosa Lara , Michel Rieutord

Interpreting the oscillations of massive and intermediate mass stars remains a challenging task. In fast rotators, the oscillation spectrum of p-modes is a superposition of sub-spectra which correspond to different types of modes, among…

Solar and Stellar Astrophysics · Physics 2019-11-26 Benjamin Evano , François Lignières , Bertrand Georgeot

Context: Rapid rotation modifies the structure of the frequency spectrum of pulsating stars, thus making mode identification difficult. Aims: We look for new forms of organisation for the frequency spectrum that can provide a basis for mode…

Astrophysics · Physics 2009-11-13 D. Reese , F. Lignières , M. Rieutord

Our knowledge of the dynamics of stars has undergone a revolution thanks to the simultaneous large amount of high-quality photometric observations collected by space-based asteroseismology and ground-based high-precision spectropolarimetry.…

Solar and Stellar Astrophysics · Physics 2021-03-24 Stéphane Mathis , Lisa Bugnet , Vincent Prat , Kyle Augustson , Savita Mathur , Rafael A. Garcia

The oscillation spectrum of pressure waves in stars can be determined by monitoring their luminosity. For rapidly rotating stars, the corresponding ray dynamics is mixed, with chaotic and regular zones in phase space. Our numerical…

Solar and Stellar Astrophysics · Physics 2019-04-22 Benjamin Evano , Bertrand Georgeot , François Lignières

We propose a new method to study the quasi-normal modes of rotating relativistic stars. Oscillations are treated as perturbations in the frequency domain of the stationary, axisymmetric background describing a rotating star. The perturbed…

General Relativity and Quantum Cosmology · Physics 2008-11-26 V. Ferrari , L. Gualtieri , S. Marassi

A new non-perturbative method to compute accurate oscillation modes in rapidly rotating stars is presented. In this paper, the effect of the centrifugal force is fully taken into account while the Coriolis force is neglected. This…

Astrophysics · Physics 2009-11-11 F. Lignieres , M. Rieutord , D. Reese

According to a recent ray-based asymptotic theory, the high-frequency p-mode spectrum of rapidly rotating stars is a superposition of frequency subsets associated with dynamically independent regions of the ray-dynamics phase space. At high…

Solar and Stellar Astrophysics · Physics 2015-05-20 F. Lignieres , B. Georgeot , J. Ballot

Parameter regions in which stars can become pulsationally unstable are found throughout the Hertzsprung-Russel diagram. Stars of high, intermediate, low and very low masses may cross various instability regions along their paths of…

Solar and Stellar Astrophysics · Physics 2015-06-11 Sonja Schuh

In solar-like stars, acoustic modes provide the main way of probing their internal structure and dynamics. Although these modes are expected to be ubiquitous in stars with convective envelopes, Kepler observations reveal that a significant…

Solar and Stellar Astrophysics · Physics 2026-04-30 Arthur Le Saux , Leïla Bessila , Stéphane Mathis

Context. The seismology of early-type stars is limited by our incomplete understanding of gravito-inertial modes. Aims. We develop a short-wavelength asymptotic analysis for gravito-inertial modes in rotating stars. Methods. The…

Solar and Stellar Astrophysics · Physics 2016-03-02 Vincent Prat , François Lignières , Jérôme Ballot

Oscillation modes of rapidly rotating stars have not yet been calculated with precision, rotational effects being generally approximated by perturbation methods. We are developing a numerical method able to account for the deformation of…

Astrophysics · Physics 2007-05-23 F. Lignières , M. Rieutord , L. Valdettaro

Acoustic modes of oscillation are affected by stellar activity, however it is unclear how starspots contribute to these changes. Here we investigate the nonmagnetic effects of starspots on global modes with angular degree $\ell \leq 2$ in…

Solar and Stellar Astrophysics · Physics 2015-05-20 Emanuele Papini , Aaron C. Birch , Laurent Gizon , Shravan M. Hanasoge

Asteroseismology has reached a level of accuracy that may allow us to detect the effect of a deep magnetic field on oscillation modes. We thus aim to develop an asymptotic theory for short-wavelength waves in radiative zones of rotating…

Solar and Stellar Astrophysics · Physics 2018-10-15 Aurélien Valade , Vincent Prat , Stéphane Mathis , Kyle Augustson

Context: Recent calculations of pulsation modes in rapidly rotating polytropic models and models based on the Self-Consistent Field method (MacGregor et al. 2007) have shown that the frequency spectrum of low degree pulsation modes can be…

Solar and Stellar Astrophysics · Physics 2015-05-13 D. R. Reese , M. J. Thompson , K. B. MacGregor , S. Jackson , A. Skumanich , T. S. Metcalfe

Asteroseismology has opened a window on the internal physics of thousands of stars, by relating oscillation spectra properties to the internal physics of stars. Mode identification, namely the process of associating a measured oscillation…

Solar and Stellar Astrophysics · Physics 2022-09-21 Giovanni Marcello Mirouh

Stellar oscillations can be of topological origin. We reveal this deep and so-far hidden property of stars by establishing a novel parallel between stars and topological insulators. We construct an hermitian problem to derive the expression…

Solar and Stellar Astrophysics · Physics 2022-11-30 Armand Leclerc , Guillaume Laibe , Pierre Delplace , Antoine Venaille , Nicolas Perez
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