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We present twenty-three transit light curves and seven occultation light curves for the ultra-short period planet WASP-43 b, in addition to eight new measurements of the radial velocity of the star. Thanks to this extensive data set, we improve significantly the parameters of the system. Notably, the largely improved precision on the stellar density (2.41+-0.08 rho_sun) combined with constraining the age to be younger than a Hubble time allows us to break the degeneracy of the stellar solution mentioned in the discovery paper. The resulting stellar mass and size are 0.717+-0.025 M_sun and 0.667+-0.011 R_sun. Our deduced physical parameters for the planet are 2.034+-0.052 M_jup and 1.036+-0.019 R_jup. Taking into account its level of irradiation, the high density of the planet favors an old age and a massive core. Our deduced orbital eccentricity, 0.0035(-0.0025,+0.0060), is consistent with a fully circularized orbit. We detect the emission of the planet at 2.09 microns at better than 11-sigma, the deduced occultation depth being 1560+-140 ppm. Our detection of the occultation at 1.19 microns is marginal (790+-320 ppm) and more observations are needed to confirm it. We place a 3-sigma upper limit of 850 ppm on the depth of the occultation at ~0.9 microns. Together, these results strongly favor a poor redistribution of the heat to the night-side of the planet, and marginally favor a model with no day-side temperature inversion., Comment: 14 pages, 6 tables, 11 figures. Accepted for publication in A&A

We present the discovery of four new transiting hot jupiters, detected mainly from SuperWASP-North and SOPHIE observations. These new planets, WASP-52b, WASP-58b, WASP-59b, and WASP-60b, have orbital periods ranging from 1.7 to 7.9 days, masses between 0.46 and 0.94 M_Jup, and radii between 0.73 and 1.49 R_Jup. Their G1 to K5 dwarf host stars have V magnitudes in the range 11.7-13.0. The depths of the transits are between 0.6 and 2.7%, depending on the target. With their large radii, WASP-52b and 58b are new cases of low-density, inflated planets, whereas WASP-59b is likely to have a large, dense core. WASP-60 shows shallow transits. In the case of WASP-52 we also detected the Rossiter-McLaughlin anomaly via time-resolved spectroscopy of a transit. We measured the sky-projected obliquity lambda = 24 (+17/-9) degrees, indicating that WASP-52b orbits in the same direction as its host star is rotating and that this prograde orbit is slightly misaligned with the stellar equator. These four new planetary systems increase our statistics on hot jupiters, and provide new targets for follow-up studies., Comment: 13 pages, 8 figures, 4 tables, accepted for publication in A&A

We report the discovery of WASP-34b, a sub-Jupiter-mass exoplanet transiting its 10.4-magnitude solar-type host star (1SWASP J110135.89-235138.4; TYC 6636-540-1) every 4.3177 days in a slightly eccentric orbit (e = 0.038 +/- 0.012). We find a planetary mass of 0.59 +/- 0.01 M_Jup and radius of 1.22 ^{+0.11}_{-0.08} R_Jup. There is a linear trend in the radial velocities of 55+/-4 m/s/y indicating the presence of a long-period third body in the system with a mass > 0.45 M_Jup at a distance of >1.2 AU from the host star. This third-body is either a low-mass star, white dwarf, or another planet. The transit depth ((R_P/R_*)^2 = 0.0126) and high impact parameter (b = 0.90) suggest that this could be the first known transiting exoplanet expected to undergo grazing transits, but with a confidence of only ~80%., 5 pages, 6 figures, accepted on 9 December 2010 by A&A Main Journal, Section 10. Planets and planetary systems

We report the discovery of WASP-43b, a hot Jupiter transiting a K7V star every 0.81 d. At 0.6-Msun the host star has the lowest mass of any star hosting a hot Jupiter. It also shows a 15.6-d rotation period. The planet has a mass of 1.8 Mjup, a radius of 0.9 Rjup, and with a semi-major axis of only 0.014 AU has the smallest orbital distance of any known hot Jupiter. The discovery of such a planet around a K7V star shows that planets with apparently short remaining lifetimes owing to tidal decay of the orbit are also found around stars with deep convection zones., 4 pages

We report the discovery of a new transiting planet in the Southern Hemisphere. It has been found by the WASP-south transit survey and confirmed photometrically and spectroscopically by the 1.2m Swiss Euler telescope, LCOGT 2m Faulkes South Telescope, the 60 cm TRAPPIST telescope and the ESO 3.6m telescope. The orbital period of the planet is 2.94 days. We find it is a gas giant with a mass of 0.88 \pm 0.10 Mj and a radius estimated at 0.96 \pm 0.05 Rj . We have also obtained spectra during transit with the HARPS spectrograph and detect the Rossiter-McLaughlin effect despite its small amplitude. Because of the low signal to noise of the effect and of a small impact parameter we cannot place a constraint on the projected spin-orbit angle. We find two confiicting values for the stellar rotation. Our determination, via spectral line broadening gives v sin I = 2.2 \pm 0.3 km/s, while another method, based on the activity level using the index log R'HK, gives an equatorial rotation velocity of only v = 1.35 \pm 0.20 km/s. Using these as priors in our analysis, the planet could either be misaligned or aligned. This should send strong warnings regarding the use of such priors. There is no evidence for eccentricity nor of any radial velocity drift with time., Comment: 13 pages, 8 figures, 7 tables, accepted for publication in A&A

We report the discovery of the low-density, transiting giant planet WASP-31b. The planet is 0.48 Jupiter masses and 1.55 Jupiter radii. It is in a 3.4-day orbit around a metal-poor, late-F-type, V = 11.7 dwarf star, which is a member of a common proper motion pair. In terms of its low density, WASP-31b is second only to WASP-17b, which is a more highly irradiated planet of similar mass., 6 pages, 5 figures, 4 tables. As accepted for publication in A&A; bibcode = 2011A&A...531A..60A