Analysis of radial fundamental-to-first overtone period ratios in the presence of near degeneracy

J. C. Suárez; R. Garridol; A. Moya

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arXiv · 0707.0821

Analysis of radial fundamental-to-first overtone period ratios in the presence of near degeneracy

J. C. Suárez·R. Garridol·A. Moya

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Abstract

In the present work we provide the preliminary results obtained when analysing the rotational Petersen diagrams when including the effects of near degeneracy. We found that near degeneracy affects significantly the fundamental-to-first overtone period ratios, showing wriggles in the Petersen diagrams. Analysis of such wriggles reveals that they are mainly caused by the avoided-crossing phenomenon. The size of wriggles seems to increase with the rotational velocity and could, in certain cases, invalidate any accurate mass and/or metallicity determinations. Nevertheless, deep analysis of near degeneracy effects may allow us to obtain additional information on the mode identification of the radial modes and their corresponding coupled pairs, which would allow us to constrain the modelling.

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J. C. Suárez, R. Garridol, A. Moya. 2007-07-05. Analysis of radial fundamental-to-first overtone period ratios in the presence of near degeneracy. https://arxiv.org/abs/0707.0821

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