Reference : WASP-50 b: a hot Jupiter transiting a moderately active solar-type star
Scientific journals : Article
Physical, chemical, mathematical & earth Sciences : Space science, astronomy & astrophysics
http://hdl.handle.net/2268/104300
WASP-50 b: a hot Jupiter transiting a moderately active solar-type star
English
Gillon, Michaël mailto [Université de Liège, Allée du 6 août 17, Sart Tilman, Liège 1, Belgium]
Doyle, A. P. [Astrophysics Group, Keele University, Staffordshire, ST5 5BG, UK]
Lendl, M. [Observatoire de Genève, Université de Genève, 51 chemin des Maillettes, 1290, Sauverny, Switzerland]
Maxted, P. F. L. [Astrophysics Group, Keele University, Staffordshire, ST5 5BG, UK]
Triaud, A H M J [Observatoire de Genève, Université de Genève, 51 chemin des Maillettes, 1290, Sauverny, Switzerland]
Anderson, D. R. [Astrophysics Group, Keele University, Staffordshire, ST5 5BG, UK]
Barros, S. C. C. [Astrophysics Research Centre, School of Mathematics & Physics, Queen's University, University Road, Belfast, BT7 1NN, UK]
Bento, J. [Department of Physics, University of Warwick, Coventry, CV4 7AL, UK]
Collier-Cameron, A. [School of Physics and Astronomy, University of St. Andrews, North Haugh, Fife, KY16 9SS, UK]
Enoch, B. [School of Physics and Astronomy, University of St. Andrews, North Haugh, Fife, KY16 9SS, UK]
Faedi, F. [Astrophysics Research Centre, School of Mathematics & Physics, Queen's University, University Road, Belfast, BT7 1NN, UK]
Hellier, C. [Astrophysics Group, Keele University, Staffordshire, ST5 5BG, UK]
Jehin, Emmanuel mailto [Université de Liège - ULg > Département d'astrophys., géophysique et océanographie (AGO) > Astrophysique et traitement de l'image]
Magain, Pierre mailto [Université de Liège - ULg > Département d'astrophys., géophysique et océanographie (AGO) > Astrophysique et traitement de l'image]
Montalban Iglesias, Josefa mailto [Université de Liège - ULg > Département d'astrophys., géophysique et océanographie (AGO) > Astrophysique stellaire théorique et astérosismologie]
Pepe, F. [Observatoire de Genève, Université de Genève, 51 chemin des Maillettes, 1290, Sauverny, Switzerland]
Pollacco, D. [Astrophysics Research Centre, School of Mathematics & Physics, Queen's University, University Road, Belfast, BT7 1NN, UK]
Queloz, D. [Observatoire de Genève, Université de Genève, 51 chemin des Maillettes, 1290, Sauverny, Switzerland]
Smalley, B. [Astrophysics Group, Keele University, Staffordshire, ST5 5BG, UK]
Segransan, D. [Observatoire de Genève, Université de Genève, 51 chemin des Maillettes, 1290, Sauverny, Switzerland]
Smith, A. M. S. [Astrophysics Group, Keele University, Staffordshire, ST5 5BG, UK]
Southworth, J. [Astrophysics Group, Keele University, Staffordshire, ST5 5BG, UK]
Udry, S. [Observatoire de Genève, Université de Genève, 51 chemin des Maillettes, 1290, Sauverny, Switzerland]
West, R. G. [Department of Physics and Astronomy, University of Leicester, Leicester, LE1 7RH, UK]
Wheatley, P. J. [Department of Physics, University of Warwick, Coventry, CV4 7AL, UK]
1-Sep-2011
Astronomy and Astrophysics
EDP Sciences
533
88
Yes (verified by ORBi)
International
0004-6361
1432-0746
Les Ulis
France
[en] techniques: spectroscopic ; planetary systems ; techniques: radial velocities ; stars: individual: WASP-50 ; techniques: photometric
[en] We report the discovery by the WASP transit survey of a giant planet in a close orbit (0.0295 ± 0.0009 AU) around a moderately bright (V = 11.6, K = 10) G9 dwarf (0.89 ± 0.08 M[SUB]&sun;[/SUB], 0.84 ± 0.03 R[SUB]&sun;[/SUB]) in the Southern constellation Eridanus. Thanks to high-precision follow-up photometry and spectroscopy obtained by the telescopes TRAPPIST and Euler, the mass and size of this planet, WASP-50 b, are well constrained to 1.47 ± 0.09 M[SUB]Jup[/SUB] and 1.15 ± 0.05 R[SUB]Jup[/SUB], respectively. The transit ephemeris is 2 455 558.6120 (±0.0002) + N × 1.955096 (±0.000005) HJD[SUB]UTC[/SUB]. The size of the planet is consistent with basic models of irradiated giant planets. The chromospheric activity (log R'[SUB]HK = -4.67[/SUB]) and rotational period (P[SUB]rot[/SUB] = 16.3 ± 0.5 days) of the host star suggest an age of 0.8 ± 0.4 Gy that is discrepant with a stellar-evolution estimate based on the measured stellar parameters (ρ[SUB]∗[/SUB] = 1.48 ± 0.10 ρ[SUB]&sun;[/SUB], T[SUB]eff[/SUB] = 5400 ± 100 K, [Fe/H] = -0.12 ± 0.08) which favors an age of 7 ± 3.5 Gy. This discrepancy could be explained by the tidal and magnetic influence of the planet on the star, in good agreement with the observations that stars hosting hot Jupiters tend to show faster rotation and magnetic activity. We measure a stellar inclination of 84[SUB]-31[SUP]+6[/SUP][/SUB] deg, disfavoring a high stellar obliquity. Thanks to its large irradiation and the relatively small size of its host star, WASP-50 b is a good target for occultation spectrophotometry, making it able to constrain the relationship between hot Jupiters' atmospheric thermal profiles and the chromospheric activity of their host stars. The photometric time-series used in this work are only available at the CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or via <A href="http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/533/A88">http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/533/A88</A>
http://hdl.handle.net/2268/104300
10.1051/0004-6361/201117198
http://adsabs.harvard.edu/abs/2011A%26A...533A..88G
http://de.arxiv.org/abs/1108.2641

File(s) associated to this reference

Fulltext file(s):

FileCommentaryVersionSizeAccess
Open access
1108.2641v1.pdfAuthor preprint490.08 kBView/Open

Bookmark and Share SFX Query

All documents in ORBi are protected by a user license.