WASP-37b: A 1.8 MJ EXOPLANET TRANSITING A METAL-POOR STAR

We report on the discovery of WASP-37b, a transiting hot Jupiter orbiting an m(v) = 12.7 G2-type dwarf, with a period of 3.577469 +/- 0.000011 d, transit epoch T-0 = 2455338.6188 +/- 0.0006 (HJD; dates throughout the paper are given in Coordinated Universal Time (UTC)), and a transit duration 0.1304(-0.0017)(+0.0018) d. The planetary companion has a mass M-p = 1.80 +/- 0.17 M-J and radius R-p = 1.16(-0.06)(+0.07) R-J, yielding a mean density of 1.15(-0.15)(+0.12) rho(J). From a spectral analysis, we find that the host star has M-star = 0.925 +/- 0.120 M-circle dot, R-star = 1.003 +/- 0.053 R-circle dot, T-eff = 5800 +/- 150 K, and [Fe/H] = -0.40 +/- 0.12. WASP-37 is therefore one of the lowest metallicity stars to host a transiting planet.

R. G. West | A. Collier Cameron | L. Hebb | D. Pollacco | I. Skillen | H. C. Stempels | F. Bouchy | B. Enoch | C. Moutou | D. Queloz | A. M. S. Smith | R. A. Street | S. Udry | I. Boisse | A. Santerne | University of Leicester | C. A. Haswell | University of Warwick | Las Cumbres Observatory Global Telescope Network | E. K. Simpson | F. Faedi | S. C. C. Barros | D. J. A. Brown | B. Smalley | I. Todd | O. W. Butters | G. Hebrard | J. McCormac | G. R. M. Miller | A. H. M. J. Triaud | D. R. Anderson | J. Bento | C. Hellier | S. Holmes | K. Horne | F. P. Keenan | T. A. Lister | P. F. L. Maxted | V. Moulds | A. J. Norton | N. Parley | F. Pepe | D. Segransan | C. A. Watson | P. J. Wheatley Queen's University Belfast | University of St Andrews | Vanderbilt University | Keele University | Institut d'Astrophysique de Paris | Laboratoire d'Astrophysique de Marseille | Isaac Newton Group of Telescopes | Observatoire de Geneve | Observatoire de Haute-Provence | The Open University | Uppsala University | R. Street | A. Santerne | C. Moutou | F. Bouchy | I. Boisse | S. Udry | D. Ségransan | I. Skillen | A. Cameron | F. Pepe | C. Watson | L. Hebb | N. Parley | D. Queloz | J. Bento | D. Pollacco | K. Horne | R. West | J. McCormac | P. Wheatley | A. Triaud | D. Anderson | S. Barros | D. Brown | F. Faedi | P. Maxted | B. Smalley | A. Norton | F. Keenan | A. Smith | C. Haswell | G. Hébrard | T. Lister | C. Hellier | B. Enoch | O. Butters | G. Miller | E. Simpson | I. Todd | V. Moulds | S. Holmes

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