- ID:
- ivo://CDS.VizieR/J/A+A/586/A75
- Title:
- Simulations of hot gas planets atmospheres
- Short Name:
- J/A+A/586/A75
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Absorption of high-energy radiation in planetary thermospheres is generally believed to lead to the formation of planetary winds. The resulting mass-loss rates can affect the evolution, particularly of small gas planets. We present 1D, spherically symmetric hydrodynamic simulations of the escaping atmospheres of 18 hot gas planets in the solar neighborhood. Our sample only includes strongly irradiated planets, whose expanded atmospheres may be detectable via transit spectroscopy using current instrumentation. The simulations were performed with the PLUTO-CLOUDY interface, which couples a detailed photoionization and plasma simulation code with a general MHD code. We study the thermospheric escape and derive improved estimates for the planetary mass-loss rates. Our simulations reproduce the temperature-pressure profile measured via sodium D absorption in HD 189733 b, but show still unexplained differences in the case of HD 209458 b. In contrast to general assumptions, we find that the gravitationally more tightly bound thermospheres of massive and compact planets, such as HAT-P-2 b are hydrodynamically stable. Compact planets dispose of the radiative energy input through hydrogen Ly alpha and free-free emission. Radiative cooling is also important in HD 189733 b, but it decreases toward smaller planets like GJ 436 b. Computing the planetary Ly alpha absorption and emission signals from the simulations, we find that the strong and cool winds of smaller planets mainly cause strong Ly alpha absorption but little emission. Compact and massive planets with hot, stable thermospheres cause small absorption signals but are strong Ly{alpha} emitters, possibly detectable with the current instrumentation. The absorption and emission signals provide a possible distinction between these two classes of thermospheres in hot gas planets. According to our results, WASP-80 and GJ 3470 are currently the most promising targets for observational follow-up aimed at detecting atmospheric Ly{alpha} absorption signals.
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Search Results
- ID:
- ivo://CDS.VizieR/J/ApJ/786/33
- Title:
- Simulations of the late stage of planet formation
- Short Name:
- J/ApJ/786/33
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Models of planet formation have shown that giant planets have a large impact on the number, masses, and orbits of terrestrial planets that form. In addition, they play an important role in delivering volatiles from material that formed exterior to the snow line (the region in the disk beyond which water ice can condense) to the inner region of the disk where terrestrial planets can maintain liquid water on their surfaces. We present simulations of the late stages of terrestrial planet formation from a disk of protoplanets around a solar-type star and we include a massive planet (from 1 M_{earth}_ to 1 M_J_) in Jupiter's orbit at ~5.2 AU in all but one set of simulations. Two initial disk models are examined with the same mass distribution and total initial water content, but with different distributions of water content. We compare the accretion rates and final water mass fraction of the planets that form. Remarkably, all of the planets that formed in our simulations without giant planets were water-rich, showing that giant planet companions are not required to deliver volatiles to terrestrial planets in the habitable zone. In contrast, an outer planet at least several times the mass of Earth may be needed to clear distant regions of debris truncating the epoch of frequent large impacts. Observations of exoplanets from radial velocity surveys suggest that outer Jupiter-like planets may be scarce, therefore, the results presented here suggest that there may be more habitable planets residing in our galaxy than previously thought.
- ID:
- ivo://CDS.VizieR/J/A+A/624/A68
- Title:
- 47 single-line eclipsing binaries BEBOP velocities
- Short Name:
- J/A+A/624/A68
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We introduce the BEBOP radial velocity survey for circumbinary planets. We initiated this survey using the CORALIE spectrograph on the Swiss Euler Telescope at La Silla, Chile. An intensive four year observing campaign commenced in 2013, targeting 47 single lined eclipsing binaries drawn from the EBLM survey for low mass eclipsing binaries. Our specific use of binaries with faint M dwarf companions avoids spectral contamination, providing observing conditions akin to single stars. By combining new BEBOP observations with existing ones from the EBLM programme, we report on the results of 1519 radial velocity measurements over timespans as long as eight years. For the best targets we are sensitive to planets down to 0.1 Jupiter masses, and our median sensitivity is 0.4 Jupiter masses. In this initial survey we do not detect any planetary mass companions. Nonetheless, we present the first constraints on the abundance of circumbinary companions, as a function of mass and period. A comparison of our results to Kepler's detections indicates a dispersion of planetary orbital inclinations less than ~10{deg}.
- ID:
- ivo://CDS.VizieR/J/A+AS/136/293
- Title:
- Sirius photographic observations
- Short Name:
- J/A+AS/136/293
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- A series of photographic observations on the components of Sirius was carried out in the years 1976-1986 at the Bosscha Observatory. We present the analysis and the results of the measurements.
- ID:
- ivo://CDS.VizieR/J/AJ/156/277
- Title:
- Sixty validated planets from K2 campaigns 5-8
- Short Name:
- J/AJ/156/277
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a uniform analysis of 155 candidates from the second year of NASA's K2 mission (Campaigns 5-8), yielding 60 statistically validated planets spanning a range of properties with median values of R_p_=2.5 R_{Earth}_, P=7.1 days, T_eq_=811 K, and J=11.3 mag. The sample includes 24 planets in 11 multiplanetary systems, as well as 18 false positives and 77 remaining planet candidates. Of particular interest are 18 planets smaller than 2 R_{Earth}_, five orbiting stars brighter than J=10 mag, and a system of four small planets orbiting the solar-type star EPIC 212157262. We compute planetary transit parameters and false-positive probabilities using a robust statistical framework and present a complete analysis incorporating the results of an intensive campaign of high-resolution imaging and spectroscopic observations. This work brings the K2 yield to over 360 planets, and by extrapolation, we expect that K2 will have discovered ~600 planets before the expected depletion of its onboard fuel in late 2018.
- ID:
- ivo://CDS.VizieR/J/ApJ/725/2017
- Title:
- Sloan i-band light curve of HAT-P-24
- Short Name:
- J/ApJ/725/2017
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We report the discovery of HAT-P-24b, a transiting extrasolar planet orbiting the moderately bright V=11.818 F8 dwarf star GSC 0774-01441, with a period P=3.3552464+/-0.0000071 days, transit epoch T_c_=2455216.97669+/-0.00024(BJD), and transit duration 3.653+/-0.025hr. The host star has a mass of 1.191+/-0.042M_{sun}_, radius of 1.317+/-0.068R_{sun}_, effective temperature 6373+/-80K, and a low metallicity of [Fe/H]=-0.16+/-0.08. The planetary companion has a mass of 0.681+/-0.031M_J_ and radius of 1.243+/-0.072R_J_ yielding a mean density of 0.439+/-0.069g/cm^3^. By repeating our global fits with different parameter sets, we have performed a critical investigation of the fitting techniques used for previous Hungarian-made Automated Telescope planetary discoveries. We find that the system properties are robust against the choice of priors.
- ID:
- ivo://CDS.VizieR/J/AJ/152/127
- Title:
- Sloan i follow-up light curves of HATS-18
- Short Name:
- J/AJ/152/127
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We report the discovery by the HATSouth network of HATS-18b: a 1.980+/-0.077M_J_, 1.337_-0.049_^+0.102^R_J_ planet in a 0.8378day orbit, around a solar analog star (mass 1.037+/-0.047M_{Sun}_ and radius 1.020_-0.031_^+0.057^R_{Sun}_) with V=14.067+/-0.040mag. The high planet mass, combined with its short orbital period, implies strong tidal coupling between the planetary orbit and the star. In fact, given its inferred age, HATS-18 shows evidence of significant tidal spin up, which together with WASP-19 (a very similar system) allows us to constrain the tidal quality factor for Sun-like stars to be in the range of 6.5<~log_10_(Q^*^/k_2_)<~7 even after allowing for extremely pessimistic model uncertainties. In addition, the HATS-18 system is among the best systems (and often the best system) for testing a multitude of star-planet interactions, be they gravitational, magnetic, or radiative, as well as planet formation and migration theories.
- ID:
- ivo://CDS.VizieR/J/ApJ/696/1950
- Title:
- Sloan iz light curves of HAT-P-10
- Short Name:
- J/ApJ/696/1950
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We report on the discovery of HAT-P-10b, one of the lowest mass (0.487+/-0.018M_J_) transiting extrasolar planets (TEPs) discovered to date by transit searches. HAT-P-10b orbits the moderately bright V=11.89 K dwarf GSC 02340-01714, with a period P=3.7224747+/-0.0000065d, transit epoch T_c_=2454759.68683+/-0.00016(BJD), and duration 0.1090+/-0.0008d. HAT-P-10b has a radius of 1.005^+0.032^_-0.027_R_J_ yielding a mean density of 0.594+/-0.052g/cm^3^. Comparing these observations with recent theoretical models we find that HAT-P-10b is consistent with a ~4.5Gyr, almost pure hydrogen and helium gas giant planet with a 10M_{earth}_ core. With an equilibrium temperature of T_eq_=1020+/-17K, HAT-P-10b is one of the coldest TEPs. Curiously, its Safronov number {Theta}=0.053+/-0.002 falls close to the dividing line between the two suggested TEP populations.
1039. SLoWPoKES catalog
- ID:
- ivo://CDS.VizieR/J/AJ/139/2566
- Title:
- SLoWPoKES catalog
- Short Name:
- J/AJ/139/2566
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the Sloan Low-mass Wide Pairs of Kinematically Equivalent Stars (SLoWPoKES), a catalog of 1342 very-wide (projected separation >~500AU), low-mass (at least one mid-K to mid-M dwarf component) common proper motion pairs identified from astrometry, photometry, and proper motions in the Sloan Digital Sky Survey. A Monte Carlo-based Galactic model is constructed to assess the probability of chance alignment for each pair; only pairs with a probability of chance alignment <=0.05 are included in the catalog.
1040. SLoWPoKES-II catalog
- ID:
- ivo://CDS.VizieR/J/AJ/150/57
- Title:
- SLoWPoKES-II catalog
- Short Name:
- J/AJ/150/57
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the Sloan Low-mass Wide Pairs of Kinematically Equivalent Stars (SLoWPoKES)-II catalog of low-mass visual binaries identified from the Sloan Digital Sky Survey (SDSS) by matching photometric distances. The candidate pairs are vetted by comparing the stellar information. The candidate pairs are vetted by comparing the stellar density at their respective Galactic positions to Monte Carlo realizations of a simulated Milky Way. In this way, we are able to identify large numbers of bona fide wide binaries without the need for proper motions. Here, 105537 visual binaries with angular separations of ~1-20" were identified, each with a probability of chance alignment of {<=}5%. This is the largest catalog of bona fide wide binaries to date, and it contains a diversity of systems--in mass, mass ratios, binary separations, metallicity, and evolutionary states--that should facilitate follow-up studies to characterize the properties of M dwarfs and white dwarfs. There is a subtle but definitive suggestion of multiple populations in the physical separation distribution, supporting earlier findings. We suggest that wide binaries are composed of multiple populations, most likely representing different formation modes. There are 141 M7 or later wide binary candidates, representing a seven-fold increase over the number currently known. These binaries are too wide to have been formed via the ejection mechanism. Finally, we found that 6% of spectroscopically confirmed M dwarfs are not included in the SDSS STAR catalog; they are misclassified as extended sources due to the presence of a nearby or partially resolved companion. The SLoWPoKES-II catalog is publicly available to the entire community on the World Wide Web via the Filtergraph data visualization portal.
