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Multisite observations of the PMS delta Scuti star V351 Ori

V. Ripepi·M. Marconi·S. Bernabei·F. Palla·F. J. G. Pinheiro·D. F. M. Folha·T. D. Oswalt·L. Terranegra·A. Arellano Ferro·X. J. Jiang·J. M. Alcalá·S. Marinoni·M. J. P. F. G. Monteiro·M. Rudkin·K. Johnston
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Abstract

We present the results of multisite observations spanning two years on the pre--main-sequence (PMS) star V351 Ori. A total of around 180 hours of observations over 29 nights have been collected, allowing us to measure five different periodicities, most likely related to the delta Scuti variability of V351 Ori. Comparison with the predictions of linear nonadiabatic radial pulsation models put stringent constraints on the stellar parameters and indicate that the distance to V351 Ori is intermediate between the lower limit measured by Hipparcos (210 pc) and that of the Orion Nebula (450 pc). However, radial pulsation models are unable to reproduce all of the observed frequencies with a single choice of (M, L, and Te), suggesting the presence of additional nonradial modes.

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V. Ripepi, M. Marconi, S. Bernabei, F. Palla, F. J. G. Pinheiro, D. F. M. Folha, T. D. Oswalt, L. Terranegra, A. Arellano Ferro, X. J. Jiang, J. M. Alcalá, S. Marinoni, M. J. P. F. G. Monteiro, M. Rudkin, K. Johnston. 2003-06-26. Multisite observations of the PMS delta Scuti star V351 Ori. https://doi.org/10.1051/0004-6361%3A20031011

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