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Description
We report the discovery by the WASP transit survey of three new hot Jupiters, WASP-68 b, WASP-73 b and WASP-88 b. WASP-68 b has a mass of 0.95+/-0.03M_Jup_, a radius of 1.24_-0.06_^+0.10^R_Jup_, and orbits a V=10.7 G0-type star (1.24+/-0.03M_{sun}_, 1.69_-0.06_^+0.11^R_{sun}_, Teff=5911+/-60K) with a period of 5.084298+/-0.000015-days. Its size is typical of hot Jupiters with similar masses. WASP-73 b is significantly more massive (1.88_-0.06_^+0.07^M_Jup_) and slightly larger (1.16_-0.08_^+0.12^R_Jup_) than Jupiter. It orbits a V=10.5 F9-type star (1.34_-0.04_^+0.05^M_{sun}_, 2.07_-0.08_^+0.19^R_{sun}_, Teff=6036+/-120K) every 4.08722+/-0.00022-days. Despite its high irradiation (2.3*10^9^erg/s/cm^2^), WASP-73 b has a high mean density (1.20_-0.30_^+0.26^{rho}_Jup_) that suggests an enrichment of the planet in heavy elements. WASP-88 b is a 0.56+/-0.08M_Jup_ planet orbiting a V=11.4 F6-type star (1.45+/-0.05M_{sun}_, 2.08_-0.06_^+0.12^R_{sun}_, Teff=6431+/-130K) with a period of 4.954000+/-0.000019-days. With a radius of 1.70_-0.07_^+0.13^R_Jup_, it joins the handful of planets with super-inflated radii. The ranges of ages we determine through stellar evolution modeling are 4.5-7.0Gyr for WASP-68, 2.8-5.7Gyr for WASP-73 and 1.8-4.3Gyr for WASP-88. WASP-73 appears to be a significantly evolved star, close to or already in the subgiant phase. WASP-68 and WASP-88 are less evolved, although in an advanced stage of core H-burning.
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