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arXiv · 1011.5882

WASP-31b: a low-density planet transiting a metal-poor, late-F-type dwarf star

D. R. Anderson·A. Collier Cameron·C. Hellier·M. Lendl·T. A. Lister·P. F. L. Maxted·D. Queloz·B. Smalley·A. M. S. Smith·A. H. M. J. Triaud·R. G. West·D. J. A. Brown·M. Gillon·F. Pepe·D. Pollacco·D. Segransan·R. A. Street·S. Udry
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Abstract

We report the discovery of the low-density, transiting giant planet WASP-31b. The planet is 0.48 Jupiter masses and 1.55 Jupiter radii. It is in a 3.4-day orbit around a metal-poor, late-F-type, V = 11.7 dwarf star, which is a member of a common proper motion pair. In terms of its low density, WASP-31b is second only to WASP-17b, which is a more highly irradiated planet of similar mass.

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D. R. Anderson, A. Collier Cameron, C. Hellier, M. Lendl, T. A. Lister, P. F. L. Maxted, D. Queloz, B. Smalley, A. M. S. Smith, A. H. M. J. Triaud, R. G. West, D. J. A. Brown, M. Gillon, F. Pepe, D. Pollacco, D. Segransan, R. A. Street, S. Udry. 2012-05-02. WASP-31b: a low-density planet transiting a metal-poor, late-F-type dwarf star. https://doi.org/10.1051/0004-6361%2F201016208

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