- 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.
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23332. WASP-44 griz light curves
- ID:
- ivo://CDS.VizieR/J/MNRAS/430/2932
- Title:
- WASP-44 griz light curves
- Short Name:
- J/MNRAS/430/2932
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present ground-based broad-band photometry of two transits in the WASP-44 planetary system obtained simultaneously through four optical (Sloan g', r', i', z') and three near-infrared (NIR; J, H, K) filters. We achieved low scatters of 1-2mmag per observation in the optical bands with a cadence of roughly 48s, but the NIR-band light curves present much greater scatter. We also observed another transit of WASP-44 b by using a Gunn r filter and telescope defocussing, with a scatter of 0.37 mmag per point and an observing cadence around 135 s. We used these data to improve measurements of the time of mid- transit and the physical properties of the system. In particular, we improved the radius measurements of the star and planet by factors of 3 and 4, respectively. We find that the radius of WASP-44 b is 1.002+/-0.033+/-0.018RJup (statistical and systematic errors, respectively), which is slightly smaller than previously thought and differs from that expected for a core-free planet. In addition, with the help of a synthetic spectrum, we investigated the theoretically predicted variation of the planetary radius as a function of wavelength, covering the range 370-2440nm. We can rule out extreme variations at optical wavelengths, but unfortunately our data are not precise enough (especially in the NIR bands) to differentiate between the theoretical spectrum and a radius which does not change with wavelength. The resulting measurements of transit mid-points were fitted with a straight line to obtain a new orbital ephemeris: T0=BJD(TDB)2455434.37642(37)+2.4238133(23)xE, where E is the number of orbital cycles after the reference epoch [the mid-point of the first transit observed by Anderson et al. (2012, Cat. J/MNRAS/422/1988)] and quantities in parentheses denote the uncertainty in the final digit of the preceding number.
23333. WASP-74 griz_s_ light curves
- 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/A+A/563/A41
- Title:
- WASP-43 OSIRIS transmission spectroscopy
- Short Name:
- J/A+A/563/A41
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We used the Gran Telescopio Canarias (GTC) instrument OSIRIS to obtain long-slit spectra in the optical range 520-1040nm of the planetary host star WASP-43 and of a reference star during a full primary transit event. We integrated the stellar flux of both stars in different wavelength regions producing several light curves. We measure a mean planet-to-star radius ratio in the white light curve of 0.15988^+0.00133^_-0.00145_. We present a tentative detection in the planet-to-star radius ratio around the NaI doublet ({lambda} 588.9, 589.5nm) when compared to the nearby continuum at the 2.9-sigma level. We find no significant excess of the measured planet-to-star radius ratio around the KI doublet ({lambda} 766.5nm, 769.9nm) when compared to the nearby continuum.
- ID:
- ivo://CDS.VizieR/J/A+A/551/A80
- Title:
- WASP-80 photometric and radial velocity data
- Short Name:
- J/A+A/551/A80
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We report the discovery of a planet transiting the star WASP-80 (1SWASP J201240.26-020838.2; 2MASS J20124017-0208391; TYC 5165-481-1; BPM 80815; V=11.9, K=8.4). Our analysis shows this is a 0.55+/-0.04M_jup_, 0.95+/-0.03R_jup_ gas giant on a circular 3.07 day orbit around a star with a spectral type between K7V and M0V. This system produces one of the largest transit depths so far reported, making it a worthwhile target for transmission spectroscopy. We find a large discrepancy between the vsini* inferred from stellar line broadening and the observed amplitude of the Rossiter-McLaughlin effect. This can be understood either by an orbital plane nearly perpendicular to the stellar spin or by an additional, unaccounted for source of broadening.
- ID:
- ivo://CDS.VizieR/J/A+A/531/A24
- Title:
- WASP-23 photometric and radial velocity data
- Short Name:
- J/A+A/531/A24
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We report the discovery of a new transiting planet in the southern hemisphere. It was 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 60cm TRAPPIST telescope, and the ESO 3.6m telescope. The orbital period of the planet is 2.94 days. We find that it is a gas giant with a mass of 0.88+/-0.10M_J_ and an estimated radius of 0.96+/-0.05R_J_. We obtained spectra during transit with the HARPS spectrograph and detect the Rossiter-McLaughlin effect despite its small amplitude.
- 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.
- ID:
- ivo://CDS.VizieR/J/ApJ/893/L29
- Title:
- WASP-4 RVs & hot Jupiter predicted period changes
- Short Name:
- J/ApJ/893/L29
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The orbital period of the hot Jupiter WASP-4b appears to be decreasing at a rate of -8.64+/-1.26ms/yr, based on transit-timing measurements spanning 12yr. Proposed explanations for the period change include tidal orbital decay, apsidal precession, and acceleration of the system along the line of sight. To investigate further, we performed new radial-velocity measurements and speckle imaging of WASP-4. The radial-velocity data show that the system is accelerating toward the Sun at a rate of -0.0422+/-0.0028m/s/day. The associated Doppler effect should cause the apparent period to shrink at a rate of -5.94+/-0.39ms/yr, comparable to the observed rate. Thus, the observed change in the transit period is mostly or entirely produced by the line-of-sight acceleration of the system. This acceleration is probably caused by a wide-orbiting companion of mass 10-300M_Jup_ and orbital distance 10-100au, based on the magnitude of the radial-velocity trend and the nondetection of any companion in the speckle images. We expect that the orbital periods of one out of three hot Jupiters will change at rates similar to WASP-4b, based on the hot-Jupiter companion statistics of Knutson et al. Continued radial-velocity monitoring of hot Jupiters is therefore essential to distinguish the effects of tidal orbital decay or apsidal precession from line-of-sight acceleration.
- ID:
- ivo://CDS.VizieR/J/MNRAS/465/3693
- Title:
- 7 WASP-South transiting exoplanets
- Short Name:
- J/MNRAS/465/3693
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We describe seven exoplanets transiting stars of brightness V=10.1-12.4. WASP-130b is a 'warm Jupiter' having an orbital period of 11.6d around a metal-rich G6 star. Its mass and radius (1.23+/-0.04M_Jup_ and 0.89+/-0.03R_Jup_) support the trend that warm Jupiters have smaller radii than hot Jupiters. WASP-131b is a bloated Saturn-mass planet (0.27M_Jup_ and 1.22R_Jup_). Its large scaleheight and bright (V=10.1) host star make it a good target for atmospheric characterization. WASP-132b (0.41M_Jup_ and 0.87R_Jup_) is among the least irradiated and coolest of WASP planets, having a 7.1-d orbit around a K4 star. WASP-139b is a 'super-Neptune' akin to HATS-7b and HATS-8b, being the lowest mass planet yet found by WASP (0.12M_Jup_ and 0.80R_Jup_). The metal-rich K0 host star appears to be anomalously dense, akin to HAT-P-11. WASP-140b is a 2.4M_Jup_ planet in an eccentric (e=0.047+/-0.004) 2.2d orbit. The planet's radius is large (1.4R_Jup_), but uncertain owing to the grazing transit (b=0.93). The 10.4d rotation period of the K0 host star suggests a young age, and the time-scale for tidal circularization is likely to be the lowest of all known eccentric hot Jupiters. WASP-141b (2.7M_Jup_, 1.2R_Jup_ and P=3.3d) and WASP-142b (0.84M_Jup_, 1.53R_Jup_ and P=2.1d) are typical hot Jupiters orbiting metal-rich F stars. We show that the period distribution within the hot-Jupiter bulge does not depend on the metallicity of the host star.
