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arXiv · 1006.5089

WASP-8b: a retrograde transiting planet in a multiple system

Didier Queloz·David Anderson·Andrew Collier Cameron·Michaël Gillon·Leslie Hebb·Coel Hellier·Pierre Maxted·Francesco Pepe·Don Pollacco·Damien Ségransan·Barry Smalley·Amaury H. M. J Triaud·Stéphane Udry·Richard West
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Abstract

We report the discovery of WASP-8, a transiting planet of 2.25+-0.08 M_Jup on a strongly inclined eccentric 8.15-day orbit, moving in a retrograde direction to the rotation of its late-G host star. Evidence is found that the star is in a multiple stellar system with two other companions. The dynamical complexity of the system indicates that it may have experienced secular interactions such as the Kozai mechanism or a formation that differs from the ``classical" disc-migration theory.

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Didier Queloz, David Anderson, Andrew Collier Cameron, Michaël Gillon, Leslie Hebb, Coel Hellier, Pierre Maxted, Francesco Pepe, Don Pollacco, Damien Ségransan, Barry Smalley, Amaury H. M. J Triaud, Stéphane Udry, Richard West. 2010-06-26. WASP-8b: a retrograde transiting planet in a multiple system. https://doi.org/10.1051/0004-6361/201014768

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