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arXiv · 2410.14482

Existence of slowly rotating bipolytropes with prolate cores

Clément Staelen·Jean-Marc Huré·Anaïs Meunier·Pauline Noé
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Abstract

We report the existence of hydrostatic equilibrium states for a composite body made of two rigidly rotating, homogeneous layers bounded by spheroidal surfaces, where the core has a prolate shape. These new configurations require an oblate envelope that spins faster than the core. No solution with a prolate envelope is found. For some parameters, the prolate core can even be at rest. Numerical experiments based on the self-consistent field method support this result in the case of heterogeneous layers with polytropic equations of state. The possible cancellation of the first gravitational moment, $J_2$, is discussed.

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Clément Staelen, Jean-Marc Huré, Anaïs Meunier, Pauline Noé. 2024-10-18. Existence of slowly rotating bipolytropes with prolate cores. https://arxiv.org/abs/2410.14482

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