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Extrasolar planets and brown dwarfs around A-F type stars III. Beta-Pictoris : looking for planets, finding pulsations

F. Galland·A. M. Lagrange·S. Udry·A. Chelli·F. Pepe·J. L. Beuzit·M. Mayor
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Abstract

In the frame of the search for extrasolar planets and brown dwarfs around early-type stars, we present the results obtained on Beta-Pictoris, which is surrounded by a circumstellar disk that is warped by the presence of a planet. We used 97 spectra acquired with CORALIE and 230 spectra acquired with HARPS to characterize the radial velocity behavior of Beta-Pictoris and to infer constraints on the presence of a planet close to this star. With these data, we were able to exclude the presence of an inner giant planet (2 MJup at a distance to the star of 0.05 AU, 9 MJup at 1 AU). We also discuss the origin of the observed radial velocity variations in terms of Delta-Scuti type pulsations.

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F. Galland, A. M. Lagrange, S. Udry, A. Chelli, F. Pepe, J. L. Beuzit, M. Mayor. 2005-10-14. Extrasolar planets and brown dwarfs around A-F type stars III. Beta-Pictoris : looking for planets, finding pulsations. https://doi.org/10.1051/0004-6361%3A20054080

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