WASP-43b: The closest-orbiting hot Jupiter

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

doi:10.1051/0004-6361/201117081

arXiv · 1104.2823

WASP-43b: The closest-orbiting hot Jupiter

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

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Abstract

We report the discovery of WASP-43b, a hot Jupiter transiting a K7V star every 0.81 d. At 0.6-Msun the host star has the lowest mass of any star hosting a hot Jupiter. It also shows a 15.6-d rotation period. The planet has a mass of 1.8 Mjup, a radius of 0.9 Rjup, and with a semi-major axis of only 0.014 AU has the smallest orbital distance of any known hot Jupiter. The discovery of such a planet around a K7V star shows that planets with apparently short remaining lifetimes owing to tidal decay of the orbit are also found around stars with deep convection zones.

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Coel Hellier, D. R. Anderson, A. Collier Cameron, M. Gillon, E. Jehin, M. Lendl, P. F. L. Maxted, F. Pepe, D. Pollacco, D. Queloz, D. Segransan, B. Smalley, A. M. S. Smith, J. Southworth, A. H. M. J. Triaud, S. Udry, R. G. West. 2011-04-14. WASP-43b: The closest-orbiting hot Jupiter. https://doi.org/10.1051/0004-6361/201117081

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