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arXiv · 2512.09395

Probing stellar rotation in the Pleiades with gravity-mode pulsators

Abstract

Due to their proximity, the Pleiades are an important benchmark open cluster. Despite its status, asteroseismic analyses of its members are rare. In particular, the gravity-mode (g-mode) pulsators, which allow inference of stellar near-core properties have not been analysed yet. We aim to identify and analyse the population of g-mode pulsators in the Pleiades. Our focus lies on the internal rotation as measured from asteroseismology to obtain a well defined sample of stellar rotation on the early main sequence. Based on full-frame images from the Transiting Exoplanet Survey Satellite (TESS), we constructed light curves for intermediate-mass Pleiades members and searched for g-mode pulsators among them. For pulsators exhibiting period spacing patterns, we determined their near-core rotation rate and buoyancy periods. For all other g-mode pulsators, we estimated the near-core rotation rate based on the dominant mode frequency to obtain a comprehensive rotation rate distribution. Among our 105 target stars, we find 28 g-mode pulsators distributed across the entire upper main sequence, 19 of which are hybrid pulsators, but only three stars exhibit period spacing patterns in the current TESS data. The near-core rotation rates in A- and early F-type members are distributed between 1 and 3 d$^{-1}$ without any clear mass-dependence. This distribution is much broader than the one in the similar open cluster NGC 2516. A comparison of the buoyancy periods shows that the Pleiades and NGC 2516 are of similar asteroseismic age. With the large population of g-mode and hybrid pulsators, the Pleiades constitute a valuable asteroseismic benchmark cluster, reaffirming its important role in stellar astrophysics.

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BibTeXRIS

D. J. Fritzewski, A. Kemp, G. Li, C. Aerts. 2025-12-10. Probing stellar rotation in the Pleiades with gravity-mode pulsators. https://doi.org/10.1051/0004-6361%2F202557416

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