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Probing the superadiabaticity of the solar convection zone with inertial modes

Published online by Cambridge University Press:  23 December 2024

Prithwitosh Dey*
Affiliation:
Max–Planck-Institut für Sonnensystemforschung, 37077 Göttingen, Germany
Yuto Bekki
Affiliation:
Max–Planck-Institut für Sonnensystemforschung, 37077 Göttingen, Germany
Laurent Gizon
Affiliation:
Max–Planck-Institut für Sonnensystemforschung, 37077 Göttingen, Germany Institut für Astrophysik, Georg–August-Universität Göttingen, 37077 Göttingen, Germany
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Abstract

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Our understanding of solar convection is incomplete. A crucial gap is the unknown superadiabaticity in the solar convection zone, δ = ▽–▽ad. Global modes of oscillations in the inertial frequency range are sensitive to δ and serve as a novel tool to explore solar convection. Here, we address the forward problem where the superadiabaticity δ(r) varies with radius. We solve the 2.5D eigenvalue problem, considering the linearized equations for momentum, mass and energy conservation with respect to a realistic solar model. We find that the frequency and eigenfunction of the m = 1 high-latitude mode are influenced by δ in the lower convection zone. Our prescribed setup suggests that the superadiabaticity in the lower half of the convection zone is below 2.4×10-7 to reach a qualitative agreement with the observed eigenfunction.

Type
Poster Paper
Copyright
© The Author(s), 2024. Published by Cambridge University Press on behalf of International Astronomical Union

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