- ID:
- ivo://CDS.VizieR/J/A+A/648/A15
- Title:
- beta Pictoris photometry
- Short Name:
- J/A+A/648/A15
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Photometric monitoring of beta Pictoris in 1981 showed anomalous fluctuations of up to 4% over several days, consistent with foreground material transiting the stellar disk. The subsequent discovery of the gas giant planet beta Pictoris b and the predicted transit of its Hill sphere to within 0.1 au projected distance of the planet provided an opportunity to search for the transit of a circumplanetary disk in this 21+/-4Myr-old planetary system. Continuous broadband photometric monitoring of beta Pictoris requires ground- based observatories at multiple longitudes to provide redundancy and to provide triggers for rapid spectroscopic followup. These observatories include the dedicated beta Pictoris monitoring observatory bRing at Sutherland and Siding Springs, the ASTEP400 telescope at Concordia, and observations from the space observatories BRITE and Hubble Space Telescope. We search the combined light curves for evidence of short period transient events caused by rings and for longer term photometric variability due to diffuse circumplanetary material. We find no photometric event that matches with the event seen in November 1981, and there is no systematic photometric dimming of the star as a function of the Hill sphere radius. We conclude that the 1981 event was not caused by the transit of a circumplanetary disk around beta Pictoris b. The upper limit on the long term variability of beta Pictoris places an upper limit of 1.8x10^22^g of dust within the Hill sphere. Circumplanetary material is either condensed into a non-transiting disk, is condensed into a disk with moons that has a small obliquity, or is below our detection threshold. This is the first time that a dedicated international campaign has mapped the Hill sphere transit of a gas giant extrasolar planet at 10 au.
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Search Results
- ID:
- ivo://CDS.VizieR/J/ApJS/66/309
- Title:
- Case low-dispersion Survey VI
- Short Name:
- J/ApJS/66/309
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Positions, estimated magnitudes, and finding charts (when needed) are provided for 183 A-F stars (including both Population I and horizontal-branch stars) contained within the region 12h00m <R.A> <13h00m and +29.0 <decl. <+34.0. These stars, whose blue magnitudes range from 5.5 to 17.5, were identified on low-dispersion, objective-prism plates taken with the Burrell Schmidt telescope.
- ID:
- ivo://CDS.VizieR/J/ApJS/71/549
- Title:
- Case low-dispersion Survey X.
- Short Name:
- J/ApJS/71/549
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Position, estimated magnitudes, and finding charts are provided for 540 A-F stars in the region 8h00m <R.A< 11h10m and +29.0 <Decl.<+43.0 (1950). The Galactic latitudes lie within the range +27 and +68. The A-F stars, with blue magnitudes between 14 and 17, were identified on low-dispersion objective-prism plates taken with the Burell Schmidt telescope. A large fraction of these A-F stars are expected to belong to Population II.
- ID:
- ivo://CDS.VizieR/III/245
- Title:
- Catalogue of H line profiles of 235 B-F stars
- Short Name:
- III/245
- Date:
- 22 Feb 2022
- Publisher:
- CDS
- Description:
- There are given 1064 profiles of the hydrogen lines H{gamma} and H{delta} for 235 B,A,F-stars obtained at the Main Stellar Spectrograph of the 6-m telescope in 1978-1986 in the course of several large observing projects. Optical density close to D=1.0 was reached for all spectra on Kodak IIaO photographic plates. The profiles are presented as smoothed intensity normalized to the level of local continuum for different distances from lines core, in {AA}. The blue and red wings of H{gamma} and H{delta} lines are averaged.
- ID:
- ivo://CDS.VizieR/J/A+A/659/A74
- Title:
- CHEOPS phase curve of WASP-189 b
- Short Name:
- J/A+A/659/A74
- Date:
- 10 Mar 2022 06:44:26
- Publisher:
- CDS
- Description:
- Gas giants orbiting close to hot and massive early-type stars can reach dayside temperatures that are comparable to those of the coldest stars. These "ultra-hot Jupiters" have atmospheres made of ions and atomic species from molecular dissociation and feature strong day-to-night temperature gradients. Photometric observations at different orbital phases provide insights on the planet atmospheric properties. We analyse the photometric observations of WASP-189 acquired with the instrument CHEOPS to derive constraints on the system architecture and the planetary atmosphere. We implement a light curve model suited for asymmetric transit shape caused by the gravity-darkened photosphere of the fast-rotating host star. We also model the reflective and thermal components of the planetary flux, the effect of stellar oblateness and light-travel time on transit-eclipse timings, the stellar activity and CHEOPS systematics. From the asymmetric transit, we measure the size of the ultra-hot Jupiter WASP-189, R_p_=1.600_-0.016_^+0.017^R_J_, with a precision of 1%, and the true orbital obliquity of the planetary system {Psi}_p_=89.6+/-1.2deg (polar orbit). We detect no significant hotspot offset from the phase curve and obtain an eclipse depth {delta}_ecl_=96.5_-5.0_^+4.5^ppm, from which we derive an upper limit on the geometric albedo: A_g_<0.48. We also find that the eclipse depth can only be explained by thermal emission alone in the case of extremely inefficient energy redistribution. Finally, we attribute the photometric variability to the stellar rotation, either through superficial inhomogeneities or resonance couplings between the convective core and the radiative envelope. Based on the derived system architecture, we predict the eclipse depth in the upcoming TESS observations to be up to ~165ppm. High-precision detection of the eclipse in both CHEOPS and TESS passbands might help disentangle between reflective and thermal contributions. We also expect the right ascension of the ascending node of the orbit to precess due to the perturbations induced by the stellar quadrupole moment J_2_ (oblateness).
- ID:
- ivo://CDS.VizieR/J/other/NatAs/5.684
- Title:
- CH3OH in the HD100546 disk
- Short Name:
- J/other/NatAs/5.
- Date:
- 17 Jan 2022 00:30:51
- Publisher:
- CDS
- Description:
- Quantifying the composition of the material in protoplanetary disks is paramount to determining the potential for exoplanetary systems to produce and support habitable environments. When considering potential habitability, complex organic molecules are of relevance, key among which is methanol (CH_3_OH). Methanol primarily forms at low temperatures via the hydrogenation of CO ice on the surface of icy dust grains and is a necessary basis for the formation of more complex species such as amino acids and proteins. We report the detection of CH_3_OH in a disk around a young, luminous A-type star, HD 100546. This disk is warm and therefore does not host an abundant reservoir of CO ice. We argue that the CH_3_OH cannot form in situ, and hence this disk has probably inherited complex-organic-molecule-rich ice from an earlier cold dark cloud phase. This is strong evidence that at least some interstellar organic material survives the disk formation process and can then be incorporated into forming planets, moons and comets. Therefore, crucial pre-biotic chemical evolution already takes place in dark star-forming clouds.
- ID:
- ivo://CDS.VizieR/J/ApJ/606/L73
- Title:
- CO emission of 5 Herbig Ae stars
- Short Name:
- J/ApJ/606/L73
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We explore the high-resolution ({Lambda}/{Delta}{Lambda}=25000;{Delta}v=12km/s) M-band (4.7-5.1{mu}m) spectra of several disk-dominated Herbig Ae (HAe) systems: AB Aur, MWC 758, MWC 480, HD 163296, and VV Ser.
- ID:
- ivo://CDS.VizieR/J/A+A/638/A59
- Title:
- delta Scuti stars with TESS
- Short Name:
- J/A+A/638/A59
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Thanks to high-precision photometric data legacy from space telescopes like CoRoT and Kepler, the scientific community could detect and characterize the power spectra of hundreds of thousands of stars. Using the scaling relations, it is possible to estimate masses and radii for solar-type pulsators. However, these stars are not the only kind of stellar objects that follow these rules: delta Scuti stars seem to be characterized with seismic indexes such as the large separation. Thanks to long-duration high-cadence TESS light curves, we analysed more than two thousand of this kind of classical pulsators. In that way, we propose the frequency at maximum power as a proper seismic index since it is directly related with the intrinsic temperature, mass and radius of the star. This parameter seems not to be affected by rotation, inclination, extinction or resonances, with the exception of the evolution of the stellar parameters. Furthermore, we can constrain rotation and inclination using the departure of temperature produced by the gravity-darkening effect. This is especially feasible for fast rotators as most of delta Scuti stars seem to be.
- ID:
- ivo://CDS.VizieR/J/AJ/157/31
- Title:
- Differential photometry & radial velocities of HATS-70
- Short Name:
- J/AJ/157/31
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We report the discovery of HATS-70b, a transiting brown dwarf at the deuterium burning limit. HATS-70b has a mass of M_p_=12.9_-1.6_^+1.8^ M_Jup_ and a radius of R_p_=1.384_-0.074_^+0.079^ R_Jup_, residing in a close-in orbit with a period of 1.89 days. The host star is a M_*_=1.78+/-0.12 M_{sun}_ A star rotating at vsinI_*_=40.61_-0.35_^+0.32^ km/s, enabling us to characterize the spectroscopic transit of the brown dwarf via Doppler tomography. We find that HATS-70b, like other massive planets and brown dwarfs previously sampled, orbits in a low projected-obliquity orbit with {lambda}=8.9_-4.5_^+5.6o^. The low obliquities of these systems is surprising given all brown dwarf and massive planets with obliquities measured orbit stars hotter than the Kraft break. This trend is tentatively inconsistent with dynamically chaotic migration for systems with massive companions, though the stronger tidal influence of these companions makes it difficult to draw conclusions on the primordial obliquity distribution of this population. We also introduce a modeling scheme for planets around rapidly rotating stars, accounting for the influence of gravity darkening on the derived stellar and planetary parameters.
- ID:
- ivo://CDS.VizieR/J/AJ/158/141
- Title:
- Differential photometry & RVs of HAT-P-69 & HAT-P-70
- Short Name:
- J/AJ/158/141
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Wide-field surveys for transiting planets are well suited to searching diverse stellar populations, enabling a better understanding of the link between the properties of planets and their parent stars. We report the discovery of HAT-P-69 b (TOI 625.01) and HAT-P-70 b (TOI 624.01), two new hot Jupiters around A stars from the Hungarian-made Automated Telescope Network (HATNet) survey that have also been observed by the Transiting Exoplanet Survey Satellite. HAT-P-69 b has a mass of 3.58_-0.58_^+0.58^ M_Jup_ and a radius of 1.676_-0.033_^+0.051^ R_Jup_ and resides in a prograde 4.79 day orbit. HAT-P-70 b has a radius of 1.87_-0.10_^+0.15^ R_Jup_ and a mass constraint of <6.78 (3{sigma}) M_Jup_ and resides in a retrograde 2.74 day orbit. We use the confirmation of these planets around relatively massive stars as an opportunity to explore the occurrence rate of hot Jupiters as a function of stellar mass. We define a sample of 47126 main-sequence stars brighter than T_mag_=10 that yields 31 giant planet candidates, including 18 confirmed planets, 3 candidates, and 10 false positives. We find a net hot Jupiter occurrence rate of 0.41+/-0.10% within this sample, consistent with the rate measured by Kepler for FGK stars. When divided into stellar mass bins, we find the occurrence rate to be 0.71+/-0.31% for G stars, 0.43+/-0.15% for F stars, and 0.26+/-0.11% for A stars. Thus, at this point, we cannot discern any statistically significant trend in the occurrence of hot Jupiters with stellar mass.
