- ID:
- ivo://CDS.VizieR/J/A+A/637/A36
- Title:
- WASP-121b optical phase curve
- Short Name:
- J/A+A/637/A36
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the analysis of TESS optical photometry of WASP-121b, which reveals the phase curve of this transiting ultra-hot Jupiter. Its hotspot is located at the sub-stellar point, showing inefficient heat transport from the dayside (2870+/-50K) to the nightside (<2500K at 3{sigma}) at the altitudes probed by TESS. The TESS eclipse depth, measured at the shortest wavelength to date for WASP-121b, confirms the strong deviation from blackbody planetary emission. Our atmospheric retrieval on the complete emission spectrum supports the presence of a temperature inversion, which can be explained by the presence of VO and possibly TiO and FeH. The strong planetary emission at short wavelengths could arise from an H^-^ continuum.
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- ID:
- ivo://CDS.VizieR/J/A+A/625/A80
- Title:
- WASP-121b secondary eclipse in 2MASS K band
- Short Name:
- J/A+A/625/A80
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Ground-based observations of the secondary eclipse in the 2MASS K band are presented for the hot Jupiter WASP-121b. These are the first occultation observations of an extrasolar planet that were carried out with an instrument attached to a 1m class telescope (the SMARTS 1.3m). We find a highly significant eclipse depth of (0.228+/-0.023)%. Together with other planet atmosphere measurements, including the Hubble Space Telescope near-infrared emission spectrum, current data support more involved atmosphere models with species producing emission and absorption features, rather than simple smooth blackbody emission. Analysis of the time difference between the primary and secondary eclipses and the durations of these events yields an eccentricity of e=0.0207+/-0.0153, which is consistent with the earlier estimates of low or zero eccentricity, but with a smaller error. Comparing the observed occultation depth in the K band with the one derived under the assumption of zero Bond albedo and full heat redistribution, we find that WASP-121b has a deeper observed occultation depth than predicted. Together with the sample of 31 systems with K-band occultation data, this observation lends further support to the idea of inefficient heat transport between the day and night sides for most of the hot Jupiters.
- ID:
- ivo://CDS.VizieR/J/A+A/623/A57
- Title:
- WASP-121 b Swift UVOT near-UV transit observations
- Short Name:
- J/A+A/623/A57
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Close-in gas planets are subject to continuous photoevaporation that can erode their volatile envelopes. Today, ongoing mass loss has been confirmed in a few individual systems via transit observations in the ultraviolet spectral range. We demonstrate that the Ultraviolet/Optical Telescope (UVOT) onboard the Neil Gehrels Swift Observatory enables photometry to a relative accuracy of about 0.5% and present the first near-UV (200-270nm, NUV) transit observations of WASP-121 b, a hot Jupiter with one of the highest predicted mass-loss rates. The data cover the orbital phases 0.85 to 1.15 with three visits. We measure a broad-band NUV transit depth of 2.10+/-0.29%. While still consistent with the optical value of 1.55%, the NUV data indicate excess absorption of 0.55% at a 1.9-sigma level. Such excess absorption is known from the WASP-12 system, and both of these hot Jupiters are expected to undergo mass loss at extremely high rates. With a CLOUDY simulation, we show that absorption lines of Fe II in a dense extended atmosphere can cause broad-band NUV absorption at the 0.5% level. Given the numerous lines of low-ionization metals, the NUV range is a promising tracer of photoevaporation in the hottest gas planets.
- ID:
- ivo://CDS.VizieR/J/AJ/157/43
- Title:
- WASP-161b, WASP-163b and WASP-170b
- Short Name:
- J/AJ/157/43
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the discovery by the WASP-South transit survey of three new transiting hot Jupiters, WASP-161 b, WASP-163 b and WASP-170 b. Follow-up radial velocities obtained with the Euler/CORALIE spectrograph and high-precision transit light curves obtained with the TRAPPIST-North, TRAPPIST-South, SPECULOOS-South, NITES, and Euler telescopes have enabled us to determine the masses and radii for these transiting exoplanets. WASP-161 b completes an orbit around its V=11.1 F6V-type host star in 5.406 days, and has a mass and radius of 2.5+/-0.2M_Jup_ and 1.14+/-0.06R_Jup_ respectively. WASP-163 b has an orbital period of 1.609-days, a mass of 1.9+/-0.2M_Jup_, and a radius of 1.2+/-0.1R_Jup_. Its host star is a V=12.5 G8-type dwarf. WASP-170 b is on a 2.344-days orbit around a G1V-type star of magnitude V=12.8. It has a mass of 1.7+/-0.2M_Jup_ and a radius of 1.14+/-0.09R_Jup_. Given their irradiations (~10^9^erg/s/cm^2^) and masses, the three new planets' sizes are in good agreement with classical structure models of irradiated giant planets.
- ID:
- ivo://CDS.VizieR/J/A+A/610/A63
- Title:
- WASP-151b, WASP-153b, WASP-156b
- Short Name:
- J/A+A/610/A63
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We report the discovery of three transiting exoplanets by the SuperWASP survey and the SOPHIE spectrograph with mass and radius determined with a precision better than 15%. WASP-151b and WASP-153b are two hot Saturns with masses, radii, densities and equilibrium temperatures of 0.31^+0.04^_-0.03_M_J_, 1.13^+0.03^_-0.03_R_J_, 0.22^+0.03^_-0.02_rho_J_ and 1,290^+20^_-10_K, and 0.39^+0.02^_-0.02_M_J_, 1.55^+0.10^_-0.08_R_J_, 0.11^+0.02^_-0.02{rho}_J_ and 1,700^+40^ _-40_K, respectively. Their host stars are early G type stars (with magV ~ 13) and their orbital periods are 4.53 and 3.33 days, respectively. WASP-156b is a Super-Neptune orbiting a K type star (magV = 11.6). It has a mass of 0.128^+0.010^_-0.009_M_J_, a radius of 0.51^+0.02^_ -0.02 R_J_, a density of 1.0^+0.1^_-0.1_{rho}_J_, an equilibrium temperature of 970^+30^_-20_K and an orbital period of 3.83 days.
- ID:
- ivo://CDS.VizieR/J/MNRAS/474/876
- Title:
- WASP-80b wavelength-binned light curves
- Short Name:
- J/MNRAS/474/876
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have performed ground-based transmission spectroscopy of the hot Jupiter orbiting the cool dwarf WASP-80 using the ACAM instrument on the William Herschel Telescope (WHT) as part of the Low-Resolution Ground-Based Exoplanet Atmosphere Survey using Transmission Spectroscopy programme. This is the third paper of a ground-based transmission spectroscopy survey of hot Jupiters using low-resolution grism spectrographs. We observed two transits of the planet and have constructed transmission spectra spanning a wavelength range of 4640-8840{AA}. Our transmission spectrum is inconsistent with a previously claimed detection of potassium in WASP-80b's atmosphere, and is instead most consistent with a haze. We also do not see evidence for sodium absorption at a resolution of 100{AA}.
- ID:
- ivo://CDS.VizieR/J/A+A/628/A115
- Title:
- WASP-12, CoRoT-1 and TrES-3 light curves
- Short Name:
- J/A+A/628/A115
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the characterization of two engineered diffusers mounted on the 2.5-meter Nordic Optical Telescope, located at Roque de Los Muchachos, Spain. To assess the reliability and the efficiency of the diffusers, we carried out several test observations of two photometric standard stars, along with observations of one primary transit observation of TrES-3b in the red (R band), one of CoRoT-1b in the blue (B band), and three secondary eclipses of WASP-12b (V band). The achieved photometric precision is in all cases within the submillimagnitude level for exposures between 25 and 180 seconds. Along with a detailed analysis of the functionality of the diffusers, we add a new transit depth measurement in the blue (B band) to the already observed transmission spectrum of CoRoT-1b, disfavoring a Rayleigh slope. We also report variability of the eclipse depth of WASP-12b in the V band. For the WASP-12b secondary eclipses, we observe a secondary depth deviation of about 5 sigma, and a difference of 6 sigma and 2.5 sigma when compared to the values reported by other authors in a similar wavelength range determined from Hubble Space Telescope data. We further speculate about the potential physical processes or causes responsible for this observed variability.
- ID:
- ivo://CDS.VizieR/J/A+A/642/A50
- Title:
- WASP-74 griz_s_ light curves
- Short Name:
- J/A+A/642/A50
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present new transit observations of the hot Jupiter WASP-74 b (Teq~1860K) using the high-resolution spectrograph HARPS-N and the multi-colour simultaneous imager MuSCAT2. We refined the orbital properties of the planet and its host star and measured its obliquity for the first time. The measured sky-projected angle between the stellar spin-axis and the orbital axis of the planet is compatible with an orbit that is well-aligned with the equator of the host star ({lambda}=0.77+/-0.99{deg}). We are not able to detect any absorption feature of H{alpha} or any other atomic spectral features in the high-resolution transmission spectra of this source owing to low S/N at the line cores. Despite previous claims regarding the presence of strong optical absorbers such as TiO and VO gases in the atmosphere of WASP-74 b, new ground-based photometry combined with a reanalysis of previously reported observations from the literature show a slope in the low-resolution transmission spectrum that is steeper than expected from Rayleigh scattering alone.
- ID:
- ivo://CDS.VizieR/J/AcA/70/203
- Title:
- WASP-148 Ground-based Photometric Observations
- Short Name:
- J/AcA/70/203
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The WASP-148 planetary system has a rare architecture with a transiting Saturn-mass planet on a tight orbit which is accompanied by a slightly more massive planet on a nearby outer orbit. Using new space-born photometry and ground-based follow-up transit observations and data available in literature, we performed modeling that accounts for gravitational interactions between both planets. Thanks to the new transit timing data for planet b, uncertainties of orbital periods and eccentricities for both planets were reduced relative to previously published values by a factor of 3-4. Variation in transit timing has an amplitude of about 20 min and can be easily followed-up with a 1-m class telescopes from the ground. An approximated transit ephemeris, which accounts for gravitational interactions with an accuracy up to 5 min, is provided. No signature of transits was found for planet c down to the Neptune-size regime. No other transiting companions were found down to a size of about 2.4 Earth radii for interior orbits. We notice, however, that the regime of terrestrial-size planets still remains unexplored in that system.
- ID:
- ivo://CDS.VizieR/J/AcA/70/1
- Title:
- WASP-18 Photometric timeseries and timing data
- Short Name:
- J/AcA/70/1
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- From its discovery, the WASP-18 system with its massive transiting planet on a tight orbit was identified as a unique laboratory for studies on tidal planet-star interactions. In an analysis of Doppler data, which include five new measurements obtained with the HIRES/Keck-I instrument between 2012 and 2018, we show that the radial velocity signal of the photosphere following the planetary tidal potential can be distilled for the host star. Its amplitude is in agreement with both theoretical predictions of the equilibrium tide approximation and an ellipsoidal modulation observed in an orbital phase curve. Assuming a circular orbit, we refine system parameters using photometric time series from TESS. With a new ground-based photometric observation, we extend the span of transit timing observations to 28 years in order to probe the rate of the orbital period shortening. Since we found no departure from a constant-period model, we conclude that the modified tidal quality parameter of the host star must be greater than 3.9e6 with 95% confidence. This result is in line with conclusions drawn from studies of the population of hot Jupiters, predicting that the efficiency of tidal dissipation is 1 or 2 orders of magnitude weaker. As the WASP-18 system is one of the prime candidates for detection of orbital decay, further timing observations are expected to push the boundaries of our knowledge on stellar interiors.
