* Astronomy

Title: The variability of the CoRoT target HD171834: gamma Dor pulsations and/or activity?
Authors: K. Uytterhoeven, P. Mathias, A. Baglin, M. Rainer, E. Poretti, P. Amado, E. Chapellier, L. Mantegazza, K. Pollard, J. C. Suarez, P. M. Kilmartin, K. H. Sato, R. A. Garcia, M. Auvergne, E. Michel, R. Samadi, C. Catala, F. Baudin

We present the preliminary results of a frequency and line-profile analysis of the CoRoT gamma Dor candidate HD171834. The data consist of 149 days of CoRoT light curves and a ground-based dataset of more than 1400 high-resolution spectra, obtained with six different instruments. Low-amplitude frequencies between 0 and 5 c/d, dominated by a frequency near 0.96 c/d and several of its harmonics, are detected. These findings suggest that HD171834 is not a mere gamma Dor pulsator and that stellar activity plays an important role in its variable behaviour. Based on CoRoT space data and on ground-based observations with ESO Telescopes at the La Silla Observatory under the ESO Large Programmes ESO LP 178.D-0361 and ESO LP 182.D-0356 (FEROS/2.2m and HARPS/3.6m), and data collected with FOCES/2.2m at the Centro Astronomico Hispano Aleman at Calar Alto, SOPHIE/1.93m at Observatoire de Haute Provence, FIES/NOT at Observatorio del Roque de los Muchachos, and HERCULES/1.0m at Mount John University Observatory.

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