Three newly discovered sub-Jupiter-mass planets: WASP-69b and WASP-84b transit active K dwarfs and WASP-70Ab transits the evolved primary of a G4+K3 binary

Anderson, D.R.; Collier Cameron, A.; Delrez, L.; Doyle, A.P.; Faedi, F.; Fumel, A.; Gillon, M.; Gómez Maqueo Chew, Y.; Hellier, C.; Jehin, E.; Lendl, M.; Maxted, P.F.L.; Pepe, F.; Pollacco, D.; Queloz, D.; Ségransan, D.; Skillen, I.; Smalley, B.; Smith, A.M.S.; Taylor, J.; Triaud, A.H.M.J.; Turner, O.D.; Udry, S.; West, R.G.

Abstract

We report the discovery of the transiting exoplanets WASP-69b, WASP-70Ab and WASP-84b, each of which orbits a bright star (V ~ 10). WASP-69b is a bloated Saturn-mass planet (0.26 MJup, 1.06 RJup) in a 3.868-d period around an active, ~1-Gyr, mid-K dwarf. ROSAT detected X-rays 60±27 arcsec from WASP-69. If the star is the source then the planet could be undergoing mass-loss at a rate of ~1012 g s-1. This is one to two orders of magnitude higher than the evaporation rate estimated for HD 209458b and HD 189733b, both of which have exhibited anomalously large Lyman a absorption during transit. WASP-70Ab is a sub-Jupiter-mass planet (0.59 MJup, 1.16 RJup) in a 3.713-d orbit around the primary of a spatially resolved, 9–10-Gyr, G4+K3 binary, with a separation of 3.3 arcsec (=800 au). WASP-84b is a sub-Jupiter-mass planet (0.69 MJup, 0.94 RJup) in an 8.523-d orbit around an active, ~1-Gyr, early-K dwarf. Of the transiting planets discovered from the ground to date, WASP-84b has the third-longest period. For the active stars WASP-69 and WASP-84, we pre-whitened the radial velocities using a low-order harmonic series. We found that this reduced the residual scatter more than did the oft-used method of pre-whitening with a fit between residual radial velocity and bisector span. The system parameters were essentially unaffected by pre-whitening.

Citation

Anderson, D., Collier Cameron, A., Delrez, L., Doyle, A., Faedi, F., Fumel, A., …West, R. (2014). Three newly discovered sub-Jupiter-mass planets: WASP-69b and WASP-84b transit active K dwarfs and WASP-70Ab transits the evolved primary of a G4+K3 binary. Monthly Notices of the Royal Astronomical Society, 445(2), 1114 -1129. https://doi.org/10.1093/mnras/stu1737

• Journal Article Type: Article
• Acceptance Date: Aug 22, 2014
• Online Publication Date: Oct 7, 2014
• Publication Date: Dec 1, 2014
• Publicly Available Date: May 26, 2023
• Journal: Monthly Notices of the Royal Astronomical Society
• Print ISSN: 0035-8711
• Publisher: Oxford University Press
• Peer Reviewed: Peer Reviewed
• Volume: 445
• Issue: 2
• Pages: 1114 -1129
• DOI: https://doi.org/10.1093/mnras/stu1737
• Keywords: techniques, photometric techniques, radial velocities planets and satellites, detection planets and satellites, individual, WASP-69b planets and satellites, individual, WASP-70Ab planets and satellites, individual, WASP-84b
• Publisher URL: http://dx.doi.org/10.1093/mnras/stu1737