- ID:
- ivo://CDS.VizieR/J/A+A/567/A8
- Title:
- WASP-46b g'r'i'z'JHK occultation light curves
- Short Name:
- J/A+A/567/A8
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We aim to construct a spectral energy distribution (SED) for the emission from the dayside atmosphere of the hot Jupiter WASP-46b and to investigate its energy budget. We observed a secondary eclipse of WASP-46b simultaneously in the g'r'i'z'JHK bands using the GROND instrument on the MPG/ESO 2.2m telescope. Eclipse depths of the acquired light curves were derived to infer the brightness temperatures at multibands that cover the SED peak. We report the first detection of the thermal emission from the dayside of WASP-46b in the K band at 4.2-sigma level and tentative detections in the H (2.5-sigma) and J (2.3-sigma) bands, with flux ratios of 0.253^+0.063^_-0.060_%, 0.194+/-0.078%, and 0.129+/-0.055%, respectively. The derived brightness temperatures (2306^+177^_-187_K, 2462^+245^_-302_K, and 2453^+198^_-258_K, respectively) are consistent with an isothermal temperature profile of 2386K, which is significantly higher than the dayside-averaged equilibrium temperature, indicative of very poor heat redistribution efficiency. We also investigate the tentative detections in the g'r'i' bands and the 3-sigma upper limit in the z' band, which might indicate the existence of reflective clouds if these tentative detections do not arise from systematics.
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- ID:
- ivo://CDS.VizieR/J/MNRAS/446/2428
- Title:
- WASP-31b:HST/Spitzer transmission spectral survey
- Short Name:
- J/MNRAS/446/2428
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present Hubble Space Telescope optical and near-IR transmission spectra of the transiting hot-Jupiter WASP-31b. The spectrum covers 0.3-1.7 {mu}m at a resolution R~70, which we combine with Spitzer photometry to cover the full-optical to IR. The spectrum is dominated by a cloud deck with a flat transmission spectrum which is apparent at wavelengths >0.52{mu}m. The cloud deck is present at high altitudes and low pressures, as it covers the majority of the expected optical Na line and near-IR H_2_O features. While Na I absorption is not clearly identified, the resulting spectrum does show a very strong potassium feature detected at the 4.2{sigma} confidence level. Broadened alkali wings are not detected, indicating pressures below ~10 mbar. The lack of Na and strong K is the first indication of a sub-solar Na/K abundance ratio in a planetary atmosphere (ln[Na/K]=-3.3+/-2.8), which could potentially be explained by Na condensation on the planet's night side, or primordial abundance variations. A strong Rayleigh scattering signature is detected at short wavelengths, with a 4{sigma} significant slope. Two distinct aerosol size populations can explain the spectra, with a smaller sub-micron size grain population reaching high altitudes producing a blue Rayleigh scattering signature on top of a larger, lower lying population responsible for the flat cloud deck at longer wavelengths. We estimate that the atmospheric circulation is sufficiently strong to mix micron size particles upwards to the required 1-10 mbar pressures, necessary to explain the cloud deck. These results further confirm the importance of clouds in hot Jupiters, which can potentially dominate the overall spectra and may alter the abundances of key gaseous species.
- ID:
- ivo://CDS.VizieR/J/A+A/530/A5
- Title:
- WASP-4b Ks-band detection of thermal emission
- Short Name:
- J/A+A/530/A5
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Secondary eclipses are a powerful tool to measure directly the thermal emission from extrasolar planets, and to constrain their type and physical parameters. We started a project to obtain reliable broad-band measurements of the thermal emission of transiting exoplanets. Ground-based high-cadence near-infrared relative photometry was used to obtain a sub-millimagnitude precision light curve of a secondary eclipse of WASP-4b -- a 1.12M_J_ hot Jupiter on a 1.34-day orbit around G7V star. The data show a clear ~10{sigma} detection of the planet's thermal emission at 2.2{mu}. The calculated thermal emission corresponds to a fractional eclipse depth of 0.185^+0.014^_-0.013_%, with a related brightness temperature in Ks of T_B_=1995+/-40K, centered at Tc=2455102.61162^+0.00071^_-0.00077_HJD. We could set a limit on the eccentricity of e*cos{omega}=0.0027+/-0.0018, compatible with a near-circular orbit. The calculated brightness temperature, and the specific models suggest a highly inefficient redistribution of heat from the day-side to the night-side of the planet, and a consequent emission mainly from the day-side. The high-cadence ground-based technique is capable of detecting the faint signal of the secondary eclipse of extrasolar planets, which makes it a valuable complement to space-based mid-IR observations.
- ID:
- ivo://CDS.VizieR/J/A+A/615/A86
- Title:
- WASP-48b Ks-band occultation lightcurves
- Short Name:
- J/A+A/615/A86
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We report a detection of thermal emission from the hot Jupiter WASP-48b in the Ks-band. We used the Wide-field Infra-red Camera on the 3.6-m Canada-France Hawaii Telescope to observe an occultation of the planet by its host star. From the resulting occultation lightcurve we find a planet-to-star contrast ratio in the Ks-band of 0.136+/-0.014% , in agreement with the value of 0.109+/-0.027% previously determined. We fit the two Ks-band occultation lightcurves simultaneously with occultation lightcurves in the H-band and the Spitzer 3.6-um and 4.5-um bandpasses, radial velocity data, and transit lightcurves. From this, we revise the system parameters and construct the spectral energy distribution (SED) of the dayside atmosphere. By comparing the SED with atmospheric models, we find that both models with and without a thermal inversion are consistent with the data. We find the planet's orbit to be consistent with circular (e<0.072 at 3 sigma).
785. WASP-71b light curve
- ID:
- ivo://CDS.VizieR/J/A+A/552/A120
- Title:
- WASP-71b light curve
- Short Name:
- J/A+A/552/A120
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We report the discovery by the WASP transit survey of a highly-irradiated, massive (2.242+/-0.080M_Jup_) 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+/-0.13R_Jup_), but 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+/-9.7degrees, 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.
- ID:
- ivo://CDS.VizieR/J/A+A/552/A2
- Title:
- WASP-19b light curves
- Short Name:
- J/A+A/552/A2
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The sample of hot Jupiters that have been studied in great detail is still growing. In particular, when the planet transits its host star, it is possible to measure the planetary radius and the planet mass (with radial velocity data). For the study of planetary atmospheres, it is essential to obtain transit and occultation measurements at multiple wavelengths. We aim to characterize the transiting hot Jupiter WASP-19b by deriving accurate and precise planetary parameters from a dedicated observing campaign of transits and occultations. We have obtained a total of 14 transit lightcurves in the r'-Gunn, I-Cousins, z'-Gunn, and I+z' filters and 10 occultation lightcurves in z'-Gunn using EulerCam on the Euler-Swiss telescope and TRAPPIST. We also obtained one lightcurve through the narrow-band NB1190 filter of HAWK-I on the VLT measuring an occultation at 1.19 micron. We performed a global MCMC analysis of all new data, together with some archive data in order to refine the planetary parameters and to measure the occultation depths in z'-band and at 1.19 micron. We measure a planetary radius of R_p_=1.376+/-0.046R_J_, a planetary mass of M_p_=1.165+/-0.068M_J_, and find a very low eccentricity of e=0.0077(-0.0032/+0.0068), compatible with a circular orbit. We have detected the z'-band occultation at 3 sigma significance and measure it to be delta_F_occ,z'=352+/-116ppm, more than a factor of 2 smaller than previously published. The occultation at 1.19 micron is only marginally constrained at delta_F_occ,NB1190=1711(-726/+745)ppm. We show that the detection of occultations in the visible range is within reach, even for 1m class telescopes if a considerable number of individual events are observed. Our results suggest an oxygen-dominated atmosphere of WASP-19b, making the planet an interesting test case for oxygen-rich planets without temperature inversion.
- ID:
- ivo://CDS.VizieR/J/A+A/606/A18
- Title:
- WASP-103b light curves
- Short Name:
- J/A+A/606/A18
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Transmission spectroscopy has become a prominent tool for characterizing the atmospheric properties of close-in transiting planets. Recent observations have revealed a remarkable diversity in exoplanet spectra, which show absorption signatures of Na, K and H_2_O, in some cases partially or fully attenuated by atmospheric aerosols. Aerosols (clouds and hazes) themselves have been detected in the transmission spectra of several planets thanks to wavelength-dependent slopes caused by the particles' scattering properties. We present an optical 550-960nm transmission spectrum of the extremely irradiated hot Jupiter WASP-103b, one of the hottest (2500K) and most massive (1.5M_J_) planets yet to be studied with this technique. WASP-103b orbits its star at a separation of less than 1.2 times the Roche limit and is predicted to be strongly tidally distorted. We have used Gemini/GMOS to obtain multi-object spectroscopy throughout three transits of WASP-103b. We used relative spectrophotometry and bin sizes between 20 and 2nm to infer the planet's transmission spectrum. We find that WASP-103b shows increased absorption in the cores of the alkali (Na, K) line features. We do not confirm the presence of any strong scattering slope as previously suggested, pointing towards a clear atmosphere for the highly irradiated, massive exoplanet WASP-103b. We constrain the upper boundary of any potential cloud deck to reside at pressure levels above 0.01bar. This finding is in line with previous studies on cloud occurrence on exoplanets which find that clouds dominate the transmission spectra of cool, low surface gravity planets while hot, high surface gravity planets are either cloud-free, or possess clouds located below the altitudes probed by transmission spectra.
- ID:
- ivo://CDS.VizieR/J/A+A/568/A81
- Title:
- WASP-117b photometry and radial velocities
- Short Name:
- J/A+A/568/A81
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We report the discovery of WASP-117b, the first planet with a period beyond 10 days found by the WASP survey. The planet has a mass of M_p_=0.2755(+/- 0.0089)M_jup_, a radius of R_p_=1.021(-0.065/+0.076)R_jup_ and is in an eccentric (e=0.302(+/-0.023)), P=10.02165(+/-0.00055)d orbit around a main-sequence F9 star. The host star's brightness (V=10.15mag) makes WASP-117 a good target for follow-up observations, and with a periastron planetary equilibrium temperature of T_eq_=1225(-39/+36)K and a low planetary mean density (rho_p_=0.259(-0.048/+0.054)rho_jup_) it is one of the best targets for transmission spectroscopy among planets with periods around 10 days. From a measurement of the Rossiter-McLaughlin effect, we infer a projected angle between the planetary orbit and stellar spin axes of beta=-44(+/-11){deg}, and we further derive an orbital obliquity of psi=69.6(+4.7/-4.1){deg}. Owing to the large orbital separation, tidal forces causing orbital circularization and realignment of the planetary orbit with the stellar plane are weak, having had little impact on the planetary orbit over the system lifetime. WASP-117b joins a small sample of transiting giant planets with well characterized orbits at periods above ~8-days.
- ID:
- ivo://CDS.VizieR/J/A+A/533/A88
- Title:
- WASP-50b photometry and radial velocities
- Short Name:
- J/A+A/533/A88
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We report the discovery by the WASP transit survey of a giant planet in a close orbit (0.0295+/-0.0009AU) around a moderately bright (V=11.6, K=10) G9 dwarf (0.89+/-0.08M_{sun}_, 0.84+/-0.03R_{sun}_) in the Southern constellation Eridanus. Thanks to high-precision follow-up photometry and spectroscopy obtained by the telescopes TRAPPIST and Euler, the mass and size of this planet, WASP-50 b, are well constrained to 1.47+/-0.09M_Jup_ and 1.15+/-0.05R_Jup_, respectively. The transit ephemeris is 2455558.6120(+/-0.0002)+Nx1.955096(+/-0.000005) HJD_UTC_. The size of the planet is consistent with basic models of irradiated giant planets.
- ID:
- ivo://CDS.VizieR/J/A+A/526/A130
- Title:
- WASP-34b photometry and radial velocities
- Short Name:
- J/A+A/526/A130
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- 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+/-0.01M_Jup_ and radius of 1.22^+0.11^_-0.08_R_Jup. There is a linear trend in the radial velocities of 55+/-4m/s/y indicating the presence of a long-period third body in the system with a mass >0.45M_Jup_ at a distance of >1.2AU 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%.
