Transiting planets from WASP-South, Euler, and TRAPPIST: WASP-68 b, WASP-73 b, and WASP-88 b, three hot Jupiters transiting evolved solar-type stars

Research output: Contribution to journalArticlepeer-review

Authors

  • L. Delrez
  • V. Van Grootel
  • D. R. Anderson
  • A. Collier-Cameron
  • A. P. Doyle
  • A. Fumel
  • M. Gillon
  • C. Hellier
  • E. Jehin
  • M. Lendl
  • M. Neveu-VanMalle
  • P. F. L. Maxted
  • F. Pepe
  • D. Pollacco
  • D. Queloz
  • D. Ségransan
  • B. Smalley
  • A. M. S. Smith
  • J. Southworth
  • S. Udry
  • R. G. West

Colleges, School and Institutes

Abstract

Using the WASP transit survey, we report the discovery of three new hot Jupiters, WASP-68 b, WASP-73 b and WASP-88 b. The planet WASP-68 b has a mass of 0.95 ± 0.03 MJup, a radius of 1.24 -0.06+0.10 RJup, and orbits a V = 10.7 G0-type star (1.24 ± 0.03 M⊙ 1.69-0.06+0.11 R⊙, Teff = 5911 ± 60 K) with a period of 5.084298 ± 0.000015 days. Its size is typical of hot Jupiters with similar masses. The planet WASP-73 b is significantly more massive (1.88-0.06+0.07 MJup) and slightly larger (1.16-0.08+0.12 RJup) than Jupiter. It orbits a V = 10.5 F9-type star (1.34-0.04+0.05 M⊙, 2.07 -0.08+0.19 R⊙, Teff = 6036 ± 120 K) every 4.08722 ± 0.00022 days. Despite its high irradiation (~2.3 x 109 erg s-1 cm-2), WASP-73 b has a high mean density (1.20-0.30+0.26 ρJup) that suggests an enrichment of the planet in heavy elements. The planet WASP-88 b is a 0.56 ± 0.08 MJup hot Jupiter orbiting a V = 11.4 F6-type star (1.45 ± 0.05 M⊙, 2.08-0.06+0.12 R⊙, Teff = 6431 ± 130 K) with a period of 4.954000 ± 0.000019 days. With a radius of 1.70 -0.07+0.13 RJup, it joins the handful of planets with super-inflated radii. The ranges of ages we determine through stellar evolution modeling are 4.5-7.0 Gyr for WASP-68, 2.8-5.7 Gyr for WASP-73 and 1.8-4.3 Gyr for WASP-88. The star WASP-73 appears to be significantly evolved, close to or already in the subgiant phase. The stars WASP-68 and WASP-88 are less evolved, although in an advanced stage of core H-burning. 

Details

Original languageEnglish
Article numberA143
Number of pages13
JournalAstronomy and Astrophysics
Volume563
Publication statusPublished - 25 Mar 2014

Keywords

  • planetary systems, techniques: photometric, techniques: radial velocities, techniques: spectroscopic