Regular modes in rotating stars

Michael Pasek (1, 2, 3) , Bertrand Georgeot (1) , F. Lignieres (2) , D. R. Reese (4)

1 ICQ - Cohérence Quantique (LPT)
2 IRAP - Institut de recherche en astrophysique et planétologie
3 LPT - Laboratoire de Physique Théorique
4 LESIA - Laboratoire d'études spatiales et d'instrumentation en astrophysique

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 dynamics to build an asymptotic theory for the subset of regular modes which are the easiest to observe and identify. Comparisons with 2D numerical simulations of oscillations in polytropic stars show that both the frequency and amplitude distributions of these modes can accurately be described by an asymptotic theory for almost all rotation rates. The spectra are mainly characterized by two quantum numbers; their extraction from observed spectra should enable one to obtain information about stellar interiors.

Domaines: Astrophysique stellaire et solaire [astro-ph.SR]; Astrophysique stellaire et solaire [astro-ph.SR]; Dynamique Chaotique [nlin.CD]

Michael Pasek, Bertrand Georgeot, F. Lignieres, D. R. Reese. Regular modes in rotating stars. Physical Review Letters, 2011, 107, pp.121101. ⟨10.1103/PhysRevLett.107.121101⟩. ⟨hal-00596764⟩