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arXiv · 0710.4068

Close-up of primary and secondary asteroseismic CoRoT targets and the ground-based follow-up observations

K. Uytterhoeven·E. Poretti·M. Rainer·L. Mantegazza·W. Zima·C. Aerts·T. Morel·A. Miglio·K. Lefever·P. J. Amado·S. Martin-Ruiz·P. Mathias·J. C. Valtier·M. Paparo·J. M. Benko·the CoRoT/SWG
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Abstract

To optimise the science results of the asteroseismic part of the CoRoT satellite mission a complementary simultaneous ground-based observational campaign is organised for selected CoRoT targets. The observations include both high-resolution spectroscopic and multi-colour photometric data. We present the preliminary results of the analysis of the ground-based observations of three targets. A line-profile analysis of 216 high-resolution FEROS spectra of the delta Sct star HD 50844 reveals more than ten pulsation frequencies in the frequency range 5-18 c/d, including possibly one radial fundamental mode (6.92 c/d). Based on more than 600 multi-colour photometric datapoints of the beta Cep star HD180642, spanning about three years and obtained with different telescopes and different instruments, we confirm the presence of a dominant radial mode nu1=5.48695 c/d, and detect also its first two harmonics. We find evidence for a second mode nu2=0.3017 c/d, possibly a g-mode, and indications for two more frequencies in the 7-8 c/d domain. From Stromgren photometry we find evidence for the hybrid delta Sct/gamma Dor character of the F0 star HD 44195, as frequencies near 3 c/d and 21 c/d are detected simultaneously in the different filters.

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K. Uytterhoeven, E. Poretti, M. Rainer, L. Mantegazza, W. Zima, C. Aerts, T. Morel, A. Miglio, K. Lefever, P. J. Amado, S. Martin-Ruiz, P. Mathias, J. C. Valtier, M. Paparo, J. M. Benko, the CoRoT/SWG. 2008-11-10. Close-up of primary and secondary asteroseismic CoRoT targets and the ground-based follow-up observations. https://doi.org/10.1088/1742-6596/118/1/012077

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