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arXiv · 1811.05292

WASP-166b: a bloated super-Neptune transiting a V = 9 star

Coel Hellier·D. R. Anderson·A. H. M. J. Triaud·F. Bouchy·A. Burdanov·A. Collier Cameron·L. Delrez·D. Ehrenreich·M. Gillon·E. Jehin·M. Lendl·E. Linder·L. D. Nielsen·P. F. L. Maxted·F. Pepe·D. Pollacco·D. Queloz·D. Segransan·B. Smalley·J. J. Spake·L. Y. Temple·S. Udry·R. G. West·A. Wyttenbach
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Abstract

We report the discovery of WASP-166b, a super-Neptune planet with a mass of 0.1 Mjup (1.9 Mnep) and a bloated radius of 0.63 Rjup. It transits a V = 9.36, F9V star in a 5.44-d orbit that is aligned with the stellar rotation axis (sky-projected obliquity angle lambda = 3 +/- 5 degrees). Variations in the radial-velocity measurements are likely the result of magnetic activity over a 12-d stellar rotation period. WASP-166b appears to be a rare object within the ``Neptune desert''.

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Coel Hellier, D. R. Anderson, A. H. M. J. Triaud, F. Bouchy, A. Burdanov, A. Collier Cameron, L. Delrez, D. Ehrenreich, M. Gillon, E. Jehin, M. Lendl, E. Linder, L. D. Nielsen, P. F. L. Maxted, F. Pepe, D. Pollacco, D. Queloz, D. Segransan, B. Smalley, J. J. Spake, L. Y. Temple, S. Udry, R. G. West, A. Wyttenbach. 2018-11-13. WASP-166b: a bloated super-Neptune transiting a V = 9 star. https://doi.org/10.1093/mnras%2Fstz1903

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