The HARPS search for southern extra-solar planets
XXI. Three new giant planets orbiting the metal-poor stars HD5388, HD181720, and HD190984

N. C. Santos, M. Mayor, W. Benz, F. Bouchy, P. Figueira, G. Lo Curto, C. Lovis, C. Melo, C. Moutou, D. Naef, F. Pepe, D. Queloz, S. G. Sousa, S. Udry

Resumo
We present the discovery of three new giant planets around three metal-deficient stars: HD5388 b (1.96M_Jup), HD181720 b (0.37_Jup), and HD190984 b (3.1_Jup). All the planets have moderately eccentric orbits (ranging from 0.26 to 0.57), and long orbital periods (from 777 to 4885 days). Two of the stars (HD181720 and HD190984) were part of a program searching for giant planets around a sample of ∼100 moderately metal-poor stars, while HD5388 was part of the volume-limited sample of the HARPS GTO program. Our discoveries suggest that giant planets in long period orbits are not uncommon around moderately metal-poor stars.

Palavras chave
planets and satellites: formation – stars: abundances – stars: fundamental parameters – planetary systems – techniques: radial velocities – techniques: spectroscopic

Notas
Based on observations collected at the La Silla Parana Observatory, ESO (Chile) with the HARPS spectrograph at the 3.6-m telescope (ESO runs ID 72.C-0488 and 082.C-0212). Tables with the radial-velocities are only available in electronic form at the CDS via anonymous ftp to cdsarc.ustrasbg.fr (130.79.128.5) or via http://cdsweb.u-strasbg.fr/cgibin/qcat?J/A+A/512/A47

Astronomy and Astrophysics
Volume 512, Página A47_1
março 2010

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