WASP-42 b and WASP-49 b: two new transiting sub-Jupiters

M. Lendl; D. R. Anderson; A. Collier-Cameron; A. P. Doyle; M. Gillon; C. Hellier; E. Jehin; T. A. Lister; P. F. L. Maxted; F. Pepe; D. Pollacco; D. Queloz; B. Smalley; D. Segransan; A. M. S. Smith; A. H. M. J. Triaud; S. Udry; R. G. West; P. J. Wheatley

doi:10.1051/0004-6361/201219585

arXiv · 1205.2757

WASP-42 b and WASP-49 b: two new transiting sub-Jupiters

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

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Abstract

We report the discovery of two new transiting planets from the WASP survey. WASP-42 b is a 0.500 +/- 0.035 M_jup planet orbiting a K1 star at a separation of 0.0548 +/- 0.0017 AU with a period of 4.9816872 +/- 7.3 x 10^-6 days. The radius of WASP-42 b is 1.080 +/- 0.057 R_jup while its equilibrium temperature is T_eq = 995 +/- 34 K. We detect some evidence for a small but non-zero eccentricity of e=0.060 +/- 0.013. WASP-49 b is a 0.378 +/- 0.027 M_jup planet around an old G6 star. It has a period of 2.7817387 +/- 5.6 x 10^-6 days and a separation of 0.0379 +/- 0.0011 AU. This planet is slightly bloated, having a radius of 1.115 +/- 0.047 R_jup and an equilibrium temperature of T_eq = 1369 +/- 39 K. Both planets have been followed up photometrically, and in total we have obtained 5 full and one partial transit light curves of WASP-42 and 4 full and one partial light curves of WASP-49 using the Euler-Swiss, TRAPPIST and Faulkes South telescopes.

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M. Lendl, D. R. Anderson, A. Collier-Cameron, A. P. Doyle, M. Gillon, C. Hellier, E. Jehin, T. A. Lister, P. F. L. Maxted, F. Pepe, D. Pollacco, D. Queloz, B. Smalley, D. Segransan, A. M. S. Smith, A. H. M. J. Triaud, S. Udry, R. G. West, P. J. Wheatley. 2012-08-01. WASP-42 b and WASP-49 b: two new transiting sub-Jupiters. https://doi.org/10.1051/0004-6361%2F201219585

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