A window on exoplanet dynamical histories: Rossiter-McLaughlin observations of WASP-13b and WASP-32b
Data(s) |
01/06/2014
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Resumo |
We present Rossiter-McLaughlin observations of WASP-13b and WASP-32b and determine the sky-projected angle between the normal of the planetary orbit and the stellar rotation axis (λ). WASP-13b and WASP-32b both have prograde orbits and are consistent with alignment with measured sky-projected angles of λ =8°^{+13}_{-12} and λ =-2°^{+17}_{-19}, respectively. Both WASP-13 and WASP-32 have Teff < 6250 K, and therefore, these systems support the general trend that aligned planetary systems are preferentially found orbiting cool host stars. A Lomb-Scargle periodogram analysis was carried out on archival SuperWASP data for both systems. A statistically significant stellar rotation period detection (above 99.9 per cent confidence) was identified for the WASP-32 system with Prot =11.6 ± 1.0 days. This rotation period is in agreement with the predicted stellar rotation period calculated from the stellar radius, R*, and vsin i if a stellar inclination of i* =90° is assumed. With the determined rotation period, the true 3D angle between the stellar rotation axis and the planetary orbit, ψ, was found to be ψ = 11° ± 14°. We conclude with a discussion on the alignment of systems around cool host stars with Teff < 6150 K by calculating the tidal dissipation time-scale. We find that systems with short tidal dissipation time-scales are preferentially aligned and systems with long tidal dissipation time-scales have a broad range of obliquities. |
Identificador | |
Idioma(s) |
eng |
Direitos |
info:eu-repo/semantics/restrictedAccess |
Fonte |
Brothwell , R D , Watson , C A , Hébrard , G , Triaud , A H M J , Cegla , H , Santerne , A , Hébrard , E , Anderson , D R , Pollacco , D , Simpson , E K , Bouchy , F , Brown , D J A , Chew , Y G M , Cameron , A C , Armstrong , D J , Barros , S C C , Bento , J , Bochinski , J , Burwitz , V , Busuttil , R , Delrez , L , Doyle , A P , Faedi , F , Fumel , A , Gillon , M , Haswell , C A , Hellier , C , Jehin , E , Kolb , U , Lendl , M , Liebig , C , Maxted , P F L , McCormac , J , Miller , G R M , Norton , A J , Pepe , F , Queloz , D , Rodríguez , J , Ségransan , D , Skillen , I , Smalley , B , Stassun , K G , Udry , S , West , R G & Wheatley , P J 2014 , ' A window on exoplanet dynamical histories: Rossiter-McLaughlin observations of WASP-13b and WASP-32b ' Monthly Notices of the Royal Astronomical Society , vol 440 , no. 4 , pp. 3392-3401 . DOI: 10.1093/mnras/stu520 |
Palavras-Chave | #techniques: photometric #techniques: radial velocities #stars: individual: WASP-13 #stars: individual: WASP-32 #planetary systems |
Tipo |
article |