- ID:
- ivo://CDS.VizieR/J/AJ/154/237
- Title:
- HARPS-N radial velocities of WASP-47
- Short Name:
- J/AJ/154/237
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present precise radial velocity observations of WASP-47, a star known to host a hot Jupiter, a distant Jovian companion, and, uniquely, two additional transiting planets in short-period orbits: a super-Earth in a ~19 hr orbit, and a Neptune in a ~9 day orbit. We analyze our observations from the HARPS-N spectrograph along with previously published data to measure the most precise planet masses yet for this system. When combined with new stellar parameters and reanalyzed transit photometry, our mass measurements place strong constraints on the compositions of the two small planets. We find that, unlike most other ultra-short-period planets, the inner planet, WASP-47 e, has a mass (6.83+/-0.66 M_{Earth}_) and a radius (1.810+/-0.027 R_{Earth}_) that are inconsistent with an Earth-like composition. Instead, WASP-47 e likely has a volatile-rich envelope surrounding an Earth-like core and mantle. We also perform a dynamical analysis to constrain the orbital inclination of WASP-47 c, the outer Jovian planet. This planet likely orbits close to the plane of the inner three planets, suggesting a quiet dynamical history for the system. Our dynamical constraints also imply that WASP-47 c is much more likely to transit than a geometric calculation would suggest. We calculate a transit probability for WASP-47 c of about 10%, more than an order of magnitude larger than the geometric transit probability of 0.6%.
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- ID:
- ivo://CDS.VizieR/J/AJ/128/1761
- Title:
- HATNET variability survey
- Short Name:
- J/AJ/128/1761
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Hungarian-made Automated Telescope Network (HATnet) is an ongoing project to detect transiting extrasolar planets using small-aperture (11cm diameter) robotic telescopes. In this paper, we present the results from using image subtraction photometry to reduce a crowded stellar field observed with one of the HATnet telescopes (HAT-5). This field was chosen to overlap with the planned Kepler mission. We obtained I-band light curves for 98,000 objects in a 67 square degree field of view centered at J2000 ({alpha},{delta})=(19h44m00.0s, +37{deg}32'00.0"), near the Galactic plane in the constellations Cygnus and Lyra. These observations include 788 exposures of 5' length over 30-days. For the brightest stars (I~8.0) we achieved a precision of 3.5mmag, falling to 0.1mag at the faint end (I~14). From these light curves we identify 1617 variable stars, of which 1439 are newly discovered.
- ID:
- ivo://CDS.VizieR/J/AJ/141/166
- Title:
- HATNet variability survey of K and M dwarfs
- Short Name:
- J/AJ/141/166
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Using light curves from the HATNet survey for transiting extrasolar planets we investigate the optical broad-band photometric variability of a sample of 27, 560 field K and M dwarfs selected by color and proper-motion (V-K>~3.0, mu>30mas/yr, plus additional cuts in J-H vs. H-Ks and on the reduced proper motion). We apply a variety of variability selection algorithms on the light curves to search for periodic and quasi-periodic variations, and for large-amplitude, long-duration flare events. To set the selection thresholds we conduct Monte Carlo simulations of light curves with realistic noise properties.
- ID:
- ivo://CDS.VizieR/J/AJ/155/114
- Title:
- HAT-TR-318-007: a double-lined M dwarf binary
- Short Name:
- J/AJ/155/114
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We report the discovery by the HATNet survey of HAT-TR-318-007, a P=3.34395390+/-0.00000020 day period detached double-lined M dwarf binary with total secondary eclipses. We combine radial velocity (RV) measurements from TRES/FLWO 1.5 m and time-series photometry from HATNet, FLWO 1.2 m, BOS 0.8 m, and NASA K2 Campaign 5, to determine the masses and radii of the component stars: M_A_=0.448+/-0.011 M_{sun}_^N^, M_B_=0.2721_-0.0042_^+0.0041^ M_{sun}_^N^, R_A_=0.4548_-0.0036_^+0.0035^ R_{sun}_^N^, and R_B_=0.2913_-0.0024_^+0.0023^ R_{sun}_^N^. We obtained a FIRE/Magellan near-infrared spectrum of the primary star during a total secondary eclipse, and we use this to obtain disentangled spectra of both components. We determine spectral types of ST_A_=M3.71+/-0.69 and ST_B_=M5.01+/-0.73 and effective temperatures of T_eff,A_=3190+/-110 K and T_eff,B_=3100+/-110 K for the primary and secondary star, respectively. We also measure a metallicity of [Fe/H]=+0.298+/-0.080 for the system. We find that the system has a small, but significant, nonzero eccentricity of 0.0136+/-0.0026. The K2 light curve shows a coherent variation at a period of 3.41315_-0.00032_^+0.00030^ days, which is slightly longer than the orbital period, and which we demonstrate comes from the primary star. We interpret this as the rotation period of the primary. We perform a quantitative comparison between the Dartmouth stellar evolution models and the seven systems, including HAT-TR-318-007, that contain M dwarfs with 0.2 M_{sun}_^N^<M<0.5 M_{sun}_^N^, have metallicity measurements, and have masses and radii determined to better than 5% precision. Discrepancies between the predicted and observed masses and radii are found for three of the systems.
- ID:
- ivo://CDS.VizieR/J/A+A/513/L3
- Title:
- H-band thermal emission of exoplanet WASP-19b
- Short Name:
- J/A+A/513/L3
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the first ground-based detection of thermal emission from an exoplanet in the H-band. Using HAWK-I on the VLT, we observed an occultation of WASP-19b by its G8V-type host star. WASP-19b is a Jupiter-mass planet with an orbital period of only 19 h, and thus, being highly irradiated, is expected to be hot. We measure an H-band occultation depth of (0.259^+0.046^_-0.044_)%, which corresponds to an H-band brightness temperature of T_H_=2580+/-125K. A cloud-free model of the planet's atmosphere, with no redistribution of energy from day-side to night-side, under predicts the planet/star flux density ratio by a factor of two. As the stellar parameters, and thus the level of planetary irradiation, are well-constrained by measurement, it is likely that our model of the planet's atmosphere is too simple.
- ID:
- ivo://CDS.VizieR/J/A+A/336/920
- Title:
- HD 163151: a new W UMa type system
- Short Name:
- J/A+A/336/920
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Table 2 contains 408 simultaneous measurements collected in each of the four uvby colours of the Stromgren photometric system for the W UMa system HD 163151. The data are magnitude differences (Du, Dv, Db, Dy, D(b-y), Dm1, Dc1) of the variable star minus comparison star in the standard system versus Heliocentric Julian Day. Tables 3, 4 and 5 are the same, but for H{beta} (65 points), Johnson B data (212 points) and Johnson V data (355 points). The comparison star is HD 166095. The origin in time is the Julian Day 2449858. The observations were carried out (by E. Rodriguez, A. Claret, J.M. Garcia, F.M. Zerbi, R. Garrido, S. Martin, C. Akan, K. Luedeke, V. Keskin, C. Ibanoglu, S. Evren, Z. Tunca, R. Pekunlu, M. Paparo, J. Nuspl, K. Krisciunas and S.Y. Jiang) in 1995 during the course of a multisite campaign. The following telescopes were used: 90cm telescope of the Sierra Nevada Observatory, Spain (uvby-H{beta} photometry); 50cm telescope at the Ege University Observatory, Turkey (BV-uvby); 50cm telescope at Piszkesteto mountain station, Konkoly Observatory, Hungary (BV); 50cm telescope at the Merate Observatory, Italy (V); 30cm telescope at Albuquerque, New Mexico, USA (V) and 15cm telescope at Mauna Kea, Hawaii, USA (V).
- ID:
- ivo://CDS.VizieR/J/A+A/607/A96
- Title:
- HD 166734 ESPRESSO spectra
- Short Name:
- J/A+A/607/A96
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- HD 166734 is an eccentric eclipsing binary system composed of two supergiant O-type stars, orbiting with a 34.5-day period. In this rare configuration for such stars, the two objects mainly evolve independently, following single-star evolution so far. This system provides a chance to study the individual parameters of two supergiant massive stars and to derive their real masses. An intensive monitoring was dedicated to HD 166734. We analyzed mid- and high-resolution optical spectra to constrain the orbital parameters of this system. We also studied its light curve for the first time, obtained in the VRI filters. Finally, we disentangled the spectra of the two stars and modeled them with the CMFGEN atmosphere code in order to determine the individual physical parameters. HD 166734 is a O7.5If+O9I(f) binary. We confirm its orbital period but we revise the other orbital parameters. In comparison to what we found in the literature, the system is more eccentric and, now, the hottest and the most luminous component is also the most massive one. The light curve exhibits only one eclipse and its analysis indicates an inclination of 63.0+/-2.7{deg}. The photometric analysis provides us with a good estimation of the luminosities of the stars, and therefore their exact positions in the Hertzsprung-Russell diagram. The evolutionary and the spectroscopic masses show good agreement with the dynamical masses of 39.5M_{sun}_ for the primary and 33.5M_{sun}_ for the secondary, within the uncertainties. The two components are both enriched in helium and in nitrogen and depleted in carbon. In addition, the primary also shows a depletion in oxygen. Their surface abundances are however not different from those derived from single supergiant stars, yielding, for both components, an evolution similar to that
- ID:
- ivo://CDS.VizieR/J/A+A/645/A25
- Title:
- HD27130 photometric light curves
- Short Name:
- J/A+A/645/A25
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The derivation of accurate and precise masses and radii is possible for eclipsing binary stars, allowing for insights into their evolution. When residing in star clusters, they provide measurements of even greater precision, along with additional information on their properties. Asteroseismic investigations of solar-like oscillations offers similar possibilities for single stars. We wish to improve the previously established properties of the Hyades eclipsing binary HD 27130 and re-assess the asteroseismic properties of the giant star {epsilon} Tau. The physical properties of these members of the Hyades can be used to constrain the helium content and age of the cluster. New multi-colour light curves were combined with multi-epoch radial velocities to yield masses and radii of HD 27130. Measurements of Teff were derived from spectroscopy and photometry, and verified using the Gaia parallax. We estimated the cluster age from re-evaluated asteroseismic properties of {epsilon} Tau while using HD 27130 to constrain the helium content. The masses, radii, and Teff of HD 27130 were found to be M=1.0245+/-0.0024M_{sun}_, R=0.9226+/-0.015R_{sun}_, Teff=5650+/-50K for the primary, and M=0.7426+/-0.0016M_{sun}_, R=0.7388+/-0.026R_{sun}_, Teff=4300+/-100K for the secondary component. Our re-evaluation of {epsilon} Tau suggests that the previous literature estimates are trustworthy and that the HIPPARCOS parallax is more reliable than the Gaia DR2 parallax. The helium content of HD 27130 and, thus, of the Hyades is found to be Y=0.27 but with a significant model dependency. Correlations with the adopted metallicity result in a robust helium enrichment law, with {DELTA}Y/{DELTA}Z close to 1.2 We estimate the age of the Hyades to be 0.9+/-0.1(stat)+/-0.1(sys)Gyr, which is in slight tension with recent age estimates based on the cluster white dwarfs. The precision of the age estimate can be much improved via asteroseismic investigations of the other Hyades giants and by future improvements to the Gaia parallax for bright stars.
- ID:
- ivo://CDS.VizieR/J/AJ/158/189
- Title:
- HD 126516 radial velocity & photometric observations
- Short Name:
- J/AJ/158/189
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- From numerous radial velocities as well as Johnson B and V differential photoelectric photometry, we have determined the orbital elements and other properties of the single-lined triple system HD 126516. This system consists of a narrow-lined F5 V star and an unseen M dwarf companion in a 2.1241 day circular orbit. The small, low-mass secondary produces detectable eclipses of the primary, and that pair has been given the variable star name V349 Vir. Variations of the center-of-mass velocity of this short-period system have an orbital period of 702.7 days or 1.92 yr and an eccentricity of 0.36. The third star is likely a K or M dwarf. From an analysis of our photometry, we conclude that the primary of HD 126516 is not a {gamma} Dor variable. Comparison with evolutionary tracks indicates that the primary is slightly metal-poor and has an age of 2.5 Gyr. The projected rotational velocity of the primary is very low, just 4 km/s, which is 10 times less than its synchronous rotational velocity. Thus, either that component's rotation is extremely non-synchronous or the inclinations of the rotational and orbital axes are very different, and so the primary has a very large spin-orbit misalignment. Because of the moderate age of the system and the fact that its orbit is already circularized, neither situation is expected theoretically.
- ID:
- ivo://CDS.VizieR/J/A+A/503/601
- Title:
- HD 17156 transit photometry & radial velocities
- Short Name:
- J/A+A/503/601
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- To improve the parameters of the HD17156 system (peculiar due to the eccentric and long orbital period of its transiting planet) and constrain the presence of stellar companions. Photometric data were acquired for 4 transits, and high precision radial velocity measurements were simultaneously acquired with SARG at TNG for one transit. The template spectra of HD 17156 was used to derive effective temperature, gravity, and metallicity. A fit of the photometric and spectroscopic data was performed to measure the stellar and planetary radii, and the spin-orbit alignment. Planet orbital elements and ephemeris were derived from the fit. Near infrared adaptive optic images was acquired with ADOPT at TNG. We have found that the star has a radius of R_S_=1.44+/-0.03R_{sun}_ and the planet R_P_=1.02+/-0.08R_{jup}_ The transit ephemeris is T_c_=2454756.73134+/-0.00020+N*21.21663+/-0.00045 BJD. The analysis of the Rossiter-Mclaughlin effect shows that the system is spin orbit aligned with an angle Beta=4.8+/-5.3deg The analysis of high resolution images has not revealed any stellar companion with projected separation between 150 and 1000 AU from HD17156. Here we present the photometric data of the transits of HD 17156b.
