This paper presents new transit photometry from the Isaac Newton Telescope of two transiting exoplanetary systems, XO-5 and WASP-82. In each case the new transit light curve is more precise than any other of that system previously published. The new
data are analysed alongside previously-published photometry and radial velocities, resulting in an improved orbital ephemeris and a refined set of system parameters in each case. The observational baseline of XO-5 is extended by very nearly four years, resulting in a determination of the orbital period of XO-5b to a precision of just 50 ms. The mass and radius of XO-5b are 1.19$pm$0.03 and 1.14$pm$0.03 times those of Jupiter, respectively. The light curve of WASP-82 is only the second published for this system. The planetary mass is 1.25$pm$0.05 $M_{rm Jup}$, and the radius is 1.71$pm$0.08 $M_{rm Jup}$.
We report the discovery from the WASP survey of two exoplanetary systems, each consisting of a Jupiter-sized planet transiting an 11th magnitude (V) main-sequence star. WASP-104b orbits its star in 1.75 d, whereas WASP-106b has the fourth-longest orb
ital period of any planet discovered by means of transits observed from the ground, orbiting every 9.29 d. Each planet is more massive than Jupiter (WASP-104b has a mass of $1.27 pm 0.05 mathrm{M_{Jup}}$, while WASP-106b has a mass of $1.93 pm 0.08 mathrm{M_{Jup}}$). Both planets are just slightly larger than Jupiter, with radii of $1.14 pm 0.04$ and $1.09 pm 0.04 mathrm{R_{Jup}}$ for WASP-104 and WASP-106 respectively. No significant orbital eccentricity is detected in either system, and while this is not surprising in the case of the short-period WASP-104b, it is interesting in the case of WASP-106b, because many otherwise similar planets are known to have eccentric orbits.
We report the discovery by the WASP transit survey of a highly-irradiated, massive (2.242 +/- 0.080 MJup) planet which transits a bright (V = 10.6), evolved F8 star every 2.9 days. The planet, WASP-71b, is larger than Jupiter (1.46 +/- 0.13 RJup), bu
t less dense (0.71 +/- 0.16 {rho}Jup). We also report spectroscopic observations made during transit with the CORALIE spectrograph, which allow us to make a highly-significant detection of the Rossiter-McLaughlin effect. We determine the sky-projected angle between the stellar-spin and planetary-orbit axes to be {lambda} = 20.1 +/- 9.7 degrees, i.e. the system is aligned, according to the widely-used alignment criteria that systems are regarded as misaligned only when {lambda} is measured to be greater than 10 degrees with 3-{sigma} confidence. WASP-71, with an effective temperature of 6059 +/- 98 K, therefore fits the previously observed pattern that only stars hotter than 6250 K are host to planets in misaligned orbits. We emphasise, however, that {lambda} is merely the sky-projected obliquity angle; we are unable to determine whether the stellar-spin and planetary-orbit axes are misaligned along the line-of-sight. With a mass of 1.56 +/- 0.07 Msun, WASP-71 was previously hotter than 6250 K, and therefore might have been significantly misaligned in the past. If so, the planetary orbit has been realigned, presumably through tidal interactions with the cooling stars growing convective zone.
Aims. We observe occultations of WASP-24b to measure brightness temperatures and to determine whether or not its atmosphere exhibits a thermal inversion (stratosphere). Methods. We observed occultations of WASP-24b at 3.6 and 4.5 {mu}m using the Spit
zer Space Telescope. It has been suggested that there is a correlation between stellar activity and the presence of
We report the discovery, from WASP and CORALIE, of a transiting exoplanet in a 1.54-d orbit. The host star, WASP-36, is a magnitude V = 12.7, metal-poor G2 dwarf (Teff = 5959 pm 134 K), with [Fe/H] = -0.26 pm 0.10. We determine the planet to have mas
s and radius respectively 2.30 pm 0.07 and 1.28 pm 0.03 times that of Jupiter. We have eight partial or complete transit light curves, from four different observatories, which allows us to investigate the potential effects on the fitted system parameters of using only a single light curve. We find that the solutions obtained by analysing each of these light curves independently are consistent with our global fit to all the data, despite the apparent presence of correlated noise in at least two of the light curves.
We report the detection of thermal emission at 4.5 and 8 micron from the planet WASP-17b. We used Spitzer to measure the system brightness at each wavelength during two occultations of the planet by its host star. By combining the resulting light cur
ves with existing transit light curves and radial velocity measurements in a simultaneous analysis, we find the radius of WASP-17b to be 2.0 Rjup, which is 0.2 Rjup larger than any other known planet and 0.7 Rjup larger than predicted by the standard cooling theory of irradiated gas giant planets. We find the retrograde orbit of WASP-17b to be slightly eccentric, with 0.0012 < e < 0.070 (3 sigma). Such a low eccentricity suggests that, under current models, tidal heating alone could not have bloated the planet to its current size, so the radius of WASP-17b is currently unexplained. From the measured planet-star flux-density ratios we infer 4.5 and 8 micron brightness temperatures of 1881 +/- 50 K and 1580 +/- 150 K, respectively, consistent with a low-albedo planet that efficiently redistributes heat from its day side to its night side.
We report ground-based observations at 0.91 microns of the occultation of the hot Jupiter WASP-33b by its A5 host star. We measure the planet to be 0.109 +/- 0.030 per cent as bright as its host star at 0.91 microns. This corresponds to a brightness
temperature, T_B = 3620 +200 -250 K, significantly higher than the zero-albedo equilibrium temperature for both isotropic re-radiation (2750 +/- 37 K) and uniform day-side only re-radiation (3271 +/- 44 K), but consistent with the zero-redistribution temperature (3515 +/- 47 K). This indicates that the heat redistribution from the day-side of WASP-33b to the night side is inefficient, and further suggest that there is immediate re-radiation, and therefore little or no redistribution, of heat within the day-side. We also detected the stellar pulsations of WASP-33, which we model as the sum of four sinusoids, with periods of between 42 and 77 minutes and amplitudes of 0.5 to 1.5 mmag.
We report the first attempt to observe the secondary eclipse of a transiting extra-solar planet at radio wavelengths. We observed HD 189733 b with the Robert C. Byrd Green Bank Telescope of the NRAO over about 5.5 hours before, during and after secon
dary eclipse, at frequencies of 307 - 347 MHz. In this frequency range, we determine the 3-sigma upper limit to the flux density to be 81 mJy. The data are consistent with no eclipse or a marginal reduction in flux at the time of secondary eclipse in all subsets of our bandwidth; the strongest signal is an apparent eclipse at the 2-sigma level in the 335.2 - 339.3 MHz region. Our observed upper limit is close to theoretical predictions of the flux density of cyclotron-maser radiation from the planet.
