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 MJup, and radii between 0.73 and 1.49 RJup. 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 WASP-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 λ = 24° +17-9, indicating that WASP-52b orbits in the same direction as its host star isrotating 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.
We present the discovery of three new transiting giant planets, first detected with the WASP telescopes, and establish their planetary nature with follow up spectroscopy and ground-based photometric ...light curves. WASP-92 is an F7 star, with a moderately inflated planet orbiting with a period of 2.17 d, which has R sub( p) = 1.461 plus or minus 0.077R sub( J) and M sub( p) = 0.805 plus or minus 0.068M sub( J). WASP-93b orbits its F4 host star every 2.73 d and has R sub( p) = 1.597 plus or minus 0.077R sub( J) and M sub( p) = 1.47 plus or minus 0.029M sub( J). WASP-118b also has a hot host star (F6) and is moderately inflated, where R sub( p) = 1.440 plus or minus 0.036R sub( J) and M sub( p) = 0.514 plus or minus 0.020M sub( J) and the planet has an orbital period of 4.05 d. They are bright targets (V = 13.18, 10.97 and 11.07, respectively) ideal for further characterization work, particularly WASP-118b, which is being observed by K2 as part of campaign 8. The WASP-93 system has sufficient angular momentum to be tidally migrating outwards if the system is near spin-orbit alignment, which is divergent from the tidal behaviour of the majority of hot Jupiters discovered.
We report the discovery of two new transiting hot Jupiters, KOI-135b and KOI-204b, which were previously identified as planetary candidates by the Kepler team, and independently confirm the planetary ...nature of Kepler-17b, recently announced by Desert et al. (2011, ApJS, 197, 14). Radial-velocity measurements, taken with the SOPHIE spectrograph at the Observatoire de Haute-Provence (France), and Kepler photometry (Q1 and Q2 data) were used to derive the orbital, stellar, and planetary parameters. KOI-135b and KOI-204b orbit their parent stars in similar to 3.02 and 3.25 days, respectively. They have approximately the same radius, R-p = 1.20 +/- 0.06 R-Jup and 1.24 +/- 0.07 R-Jup, but different masses M-p = 3.23 +/- 0.19 M-Jup and 1.02 +/- 0.07 M-Jup. As a consequence, their bulk densities differ by a factor of four, rho(p) = 2.33 +/- 0.36 g cm(-3) (KOI-135b) and 0.65 +/- 0.12 g cm(-3) (KOI-204b), meaning that their interior structures are different. All three planets orbit metal-rich stars with Fe/H similar to 0.3 dex. Our SOPHIE spectra of Kepler-17 were used both to measure the radial-velocity variations and to determine the stellar atmospheric parameters, allowing us to refine the characterisation of the planetary system. In particular we found the radial-velocity semi-amplitude and the stellar mass to be respectively slightly smaller and larger than in Desert et al. These two quantities, however, compensate and lead to a fully consistent planetary mass. Our analysis gives M-p = 2.47 +/- 0.10 M-Jup and R-p = 1.33 +/- 0.04 R-Jup. We found evidence of a younger age for this planetary system, t \textless 1.8 Gyr, which is supported by both evolutionary tracks and gyrochronology. Finally, we confirm the detection of the optical secondary eclipse by Desert et al. and also find the brightness phase variation with the Q1 and Q2 Kepler data. The latter indicates a low redistribution of stellar heat to the night side (\textless16% at 1-sigma), if the optical planetary occultation comes entirely from thermal flux. The geometric albedo is A(g) \textless 0.12 (1-sigma).
We report the measurement of the spin-orbit angle of the extra-solar planets HAT-P-8 b, HAT-P-9 b, HAT-P-16 b, and HAT-P-23 b, based on spectroscopic observations performed at the Observatoire de ...Haute-Provence with the SOPHIE spectrograph on the 1.93-m telescope. Radial velocity measurements of the Rossiter-McLaughlin effect show the detection of an apparent prograde, aligned orbit for all systems. The projected spin-orbit angles are found to be λ = −17°\hbox{$^{+9.2}_{-11.5}$}+9.2-11.5, −16° ± 8°, –10° ± 16°, and +15° ± 22° for HAT-P-8, HAT-P-9, HAT-P-16, and HAT-P-23, respectively, with corresponding projected rotational velocities of 14.5 ± 0.8, 12.5 ± 1.8, 3.9 ± 0.8, and 7.8 ± 1.6 km s-1. These new results increase to 37 the number of accurately measured spin-orbit angles in transiting extrasolar systems. We conclude by drawing a tentative picture of the global behaviour of orbital alignement, involving the complexity and diversity of possible mechanisms.
We report on spectroscopic and photometric observations through transits of the exoplanets WASP-22b and WASP-26b, intended to determine the systems’ spin-orbit angles. We combine these data with ...existing data to refine the system parameters. We measure a sky-projected spin-orbit angle of 22 ± 16° for WASP-22b, showing the planet’s orbit to be prograde and, perhaps, slightly misaligned. We do not detect the Rossiter-McLaughlin effect of WASP-26b due to its low amplitude and observation noise. We place 3-σ upper limits on orbital eccentricity of 0.063 for WASP-22b and 0.050 for WASP-26b. After refining the drift in the systemic velocity of WASP-22 found by Maxted et al. (2010, AJ, 140, 2007), we find the third body in the system to have a minimum-mass of 5.3 ± 0.3 MJup (a3 / 5 AU)2, where a3 is the orbital distance of the third body.
We present new radial velocity measurements of eight stars that were secured with the spectrograph SOPHIE at the 193 cm telescope of the Haute-Provence Observatory. The measurements allow detecting ...and characterizing new giant extrasolar planets. The host stars are dwarfs of spectral types between F5 and K0 and magnitudes of between 6.7 and 9.6; the planets have minimum masses Mp sin i of between 0.4 to 3.8 MJup and orbitalperiods of several days to several months. The data allow only single planets to be discovered around the first six stars (HD 143105, HIP 109600, HD 35759, HIP 109384, HD 220842, and HD 12484), but one of them shows the signature of an additional substellar companion in the system. The seventh star, HIP 65407, allows the discovery of two giant planets that orbit just outside the 12:5 resonance in weak mutual interaction. The last star, HD 141399, was already known to host a four-planet system; our additional data and analyses allow new constraints to be set on it. We present Keplerian orbits of all systems, together with dynamical analyses of the two multi-planet systems. HD 143105 is one of the brightest stars known to host a hot Jupiter, which could allow numerous follow-up studies to be conducted even though this is not a transiting system. The giant planets HIP 109600b, HIP 109384b, and HD 141399c are located in the habitable zone of their host star.
We present high-precision radial-velocity measurements of three solar-type stars: HD 13908, HD 159243, and HIP 91258. The observations were made with the SOPHIE spectrograph at the 1.93 m telescope ...of the Observatoire de Haute-Provence (France). They show that these three bright stars host exoplanetary systems composed of at least two companions. HD 13908 b is a planet with a minimum mass of 0.865 ± 0.035MJup on a circular orbit with a period of 19.382 ± 0.006 days. There is an outer massive companion in the system with a period of 931 ± 17 days, e = 0.12 ± 0.02, and a minimum mass of 5.13 ± 0.25MJup . The star HD 159243 also has two detected companions with respective masses, periods, and eccentricities of Mp= 1.13 ± 0.05 and 1.9 ± 0.13MJup , P = 12.620 ± 0.004 and 248.4 ± 4.9 days, and e = 0.02 ± 0.02 and 0.075 ± 0.05. Finally, the star HIP 91258 has a planetary companion with a minimum mass of 1.068 ± 0.038MJup , an orbital period of 5.0505 ± 0.0015 days, and a quadratic trend indicating an outer planetary or stellar companion that is as yet uncharacterized. The planet-hosting stars HD 13908, HD 159243, and HIP 91258 are main-sequence stars of spectral types F8V, G0V, and G5V, respectively, with moderate activity levels. HIP 91258 is slightly over-metallic, while the other two stars have solar-like metallicity. The three systems are discussed in the frame of formation and dynamical evolution models of systems composed of several giant planets.
In this paper we report a new transiting warm giant planet: KOI-1257 b. It was first detected in photometry as a planet-candidate by the Kepler space telescope and then validated thanks to a radial ...velocity :follow-up with the SOPHIE spectrograph. It orbits its host star with a period of 86,647661 d +/- 3 s and a high eccentricity of 0.772 +/- 0.045. The planet transits the main star of a metal-rich, relatively old binary system With stars of mass of 0.99 +/- 0.05 M-circle dot and 0.70 +/- 0.07 M-circle dot for the primary and secondary, respectively. This binary system is constrained thanks to a self-consistent modelling of the Kepler transit light curve; the SOPHIE radial velocities; line bisector and full-width half maximum (FWHM) variations, and the spectral energy distribution. However, future observations are needed to confirm it. The PASTIS fully-Bayesian software was used to validate the nature of the planet and to determine which star of the binary system is the transit host. By accounting for the dilution from the binary both in photometry and in radial velocity, we find that the planet has a mass of 1.45 +/- 0.35 M-4, and a radius of 0.94(4) +/- 0.12 R-4 and thus a bulk density of 2.1 +/- 1.2 g cm(-3). The planet has an equilibrium temperature of 511 +/- 50K, making it one of the few known members of the warm-Jupiter population. The HARPS-N spectrograph was also used to observe a transit of KOI-1257 b, simultaneously with a joint amateur and professional photometric follow up, with the aim of constraining the orbital obliquity of the planet. However, the Rossiter-McLaughlin effect was not clearly detected, resulting in poor constraints on the orbital obliquity of the planet.
We present new radial velocity measurements of eight stars that were secured with the spectrograph SOPHIE at the 193 cm telescope of the Haute-Provence Observatory. The measurements allow detecting ...and characterizing new giant extrasolar planets. The host stars are dwarfs of spectral types between F5 and K0 and magnitudes of between 6.7 and 9.6; the planets have minimum masses M sub(p) sin i of between 0.4 to 3.8 M sub(Jup) and orbitalperiods of several days to several months. The data allow only single planets to be discovered around the first six stars (HD143105, HIP109600, HD35759, HIP109384, HD220842, and HD12484), but one of them shows the signature of an additional substellar companion in the system. The seventh star, HIP65407, allows the discovery of two giant planets that orbit just outside the 12:5 resonance in weak mutual interaction. The last star, HD141399, was already known to host a four-planet system; our additional data and analyses allow new constraints to be set on it. We present Keplerian orbits of all systems, together with dynamical analyses of the two multi-planet systems. HD143105 is one of the brightest stars known to host a hot Jupiter, which could allow numerous follow-up studies to be conducted even though this is not a transiting system. The giant planets HIP109600b, HIP109384b, and HD141399c are located in the habitable zone of their host star.
Aims. We present the discovery and characterisation of the exoplanets WASP-113b and WASP-114b by the WASP surveys, SOPHIE and CORALIE. Methods. The planetary nature of the systems was established by ...performing follow-up photometric and spectroscopic observations. The follow-up data were combined with the WASP-photometry and analysed with an MCMC code to obtain system parameters. Results. The host stars WASP-113 and WASP-114 are very similar. They are both early G-type stars with an effective temperature of ~5900 K, Fe/H ~ 0.12, and log g~ 4.1 dex. However, WASP-113 is older than WASP-114. Although the planetary companions have similar radii, WASP-114b is almost four times heavier than WASP-113b. WASP-113b has a mass of 0.48 MJup and an orbital period of ~4.5 days; WASP-114b has a mass of 1.77 MJup and an orbital period of ~1.5 days. Both planets have inflated radii, in particular WASP-113 with a radius anomaly of ℜ = 0.35. The high scale height of WASP-113b (~950 km) makes it a good target for follow-up atmospheric observations.
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