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arXiv · 2609.08046

Tidally perturbed pulsations in OO Dra

Niveditha Parthasarathy·Mikhail Kovalev·Randa Asa'd
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Abstract

We perform a pulsation analysis of OO Dra using Light Curve data from TESS and present the first identification of six dipole modes as doublets from the primary star in OO Dra. The phases and amplitudes of these pulsation modes were analytically reconstructed. Among the six identified doublets, four are pulsating in $Y_{10x}$ mode with pulsation axis along the tidal axis, and two in $Y_{10y}$ with a pulsation axis orthogonal to tidal axis and the angular momentum axis. Our findings suggest that the primary star in a non-synchronized, post mass-transfer OO Dra could be a tidally tilted $\delta$ Scuti pulsator.

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Niveditha Parthasarathy, Mikhail Kovalev, Randa Asa'd. 2026-09-07. Tidally perturbed pulsations in OO Dra. https://arxiv.org/abs/2609.08046

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