- ID:
- ivo://CDS.VizieR/J/ApJ/745/19
- Title:
- Binary systems in Taurus-Auriga
- Short Name:
- J/ApJ/745/19
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The past decade has seen a revolution in our understanding of protoplanetary disk evolution and planet formation in single-star systems. However, the majority of solar-type stars form in binary systems, so the impact of binary companions on protoplanetary disks is an important element in our understanding of planet formation. We have compiled a combined multiplicity/disk census of Taurus-Auriga, plus a restricted sample of close binaries in other regions, in order to explore the role of multiplicity in disk evolution. Our results imply that the tidal influence of a close (<=40AU) binary companion significantly hastens the process of protoplanetary disk dispersal, as ~2/3 of all close binaries promptly disperse their disks within <~1Myr after formation. However, prompt disk dispersal only occurs for a small fraction of wide binaries and single stars, with ~80%-90% retaining their disks for at least ~2-3Myr (but rarely for more than ~5Myr). Our new constraints on the disk clearing timescale have significant implications for giant planet formation; most single stars have 3-5Myr within which to form giant planets, whereas most close binary systems would have to form giant planets within <~1Myr. If core accretion is the primary mode for giant planet formation, then gas giants in close binaries should be rare. Conversely, since almost all single stars have a similar period of time within which to form gas giants, their relative rarity in radial velocity (RV) surveys indicates either that the giant planet formation timescale is very well matched to the disk dispersal timescale or that features beyond the disk lifetime set the likelihood of giant planet formation.
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Search Results
- ID:
- ivo://CDS.VizieR/J/MNRAS/414/108
- Title:
- Calibrator of exoplanet-host stars
- Short Name:
- J/MNRAS/414/108
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Phase-referenced interferometric astrometry offers the possibility to look for exoplanets around bright stars. Instruments like PRIMA (Phase-Referenced Imaging and Micro-arcsecond Astrometry) will measure the astrometric wobble of a candidate star due to an exoplanet relative to a close-by 'calibrator' star, located within the instrument's observing field (1-arcmin in the PRIMA case). Stars with already known exoplanets will constitute the first targets for this technique, as it will provide a way to further specify the characteristics of the known exoplanets, such as the inclinations. The main requirement is to have a calibrator in the vicinity of the star. We provide here a list of calibrators for all stars with known exoplanets obtained using data mining and Virtual Observatory techniques. This list is available online and revised regularly. The calibrators are found from catalogues available at Centre de Donnees astronomiques de Strasbourg (CDS) using the SearchCal software developed at Jean-Marie Mariotti Center (JMMC). In our test case, the calibrators are found within 1 arcmin angular distance for approximately 50 per cent of the stars tested, and often closer. They are all faint objects from the Two Micron All Sky Survey (2MASS) with K magnitudes between 13 and 15. A list of the most promising targets is also given.
- ID:
- ivo://CDS.VizieR/J/AJ/154/109
- Title:
- California-Kepler Survey (CKS). III. Planet radii
- Short Name:
- J/AJ/154/109
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The size of a planet is an observable property directly connected to the physics of its formation and evolution. We used precise radius measurements from the California-Kepler Survey to study the size distribution of 2025 Kepler planets in fine detail. We detect a factor of >=2 deficit in the occurrence rate distribution at 1.5-2.0R_{Earth}_. This gap splits the population of close-in (P<100days) small planets into two size regimes: R_P_<1.5R_{Earth}_ and R_P_=2.0--3.0R_{Earth}_, with few planets in between. Planets in these two regimes have nearly the same intrinsic frequency based on occurrence measurements that account for planet detection efficiencies. The paucity of planets between 1.5 and 2.0R_{Earth}_ supports the emerging picture that close-in planets smaller than Neptune are composed of rocky cores measuring 1.5R_{Earth}_ or smaller with varying amounts of low-density gas that determine their total sizes.
- ID:
- ivo://CDS.VizieR/J/AJ/154/108
- Title:
- California-Kepler Survey (CKS). II. Properties
- Short Name:
- J/AJ/154/108
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present stellar and planetary properties for 1305 Kepler Objects of Interest hosting 2025 planet candidates observed as part of the California-Kepler Survey. We combine spectroscopic constraints, presented in Paper I, with stellar interior modeling to estimate stellar masses, radii, and ages. Stellar radii are typically constrained to 11%, compared to 40% when only photometric constraints are used. Stellar masses are constrained to 4%, and ages are constrained to 30%. We verify the integrity of the stellar parameters through comparisons with asteroseismic studies and Gaia parallaxes. We also recompute planetary radii for 2025 planet candidates. Because knowledge of planetary radii is often limited by uncertainties in stellar size, we improve the uncertainties in planet radii from typically 42% to 12%. We also leverage improved knowledge of stellar effective temperature to recompute incident stellar fluxes for the planets, now precise to 21%, compared to a factor of two when derived from photometry.
- ID:
- ivo://CDS.VizieR/J/AJ/154/107
- Title:
- California-Kepler Survey (CKS). I. 1305 stars
- Short Name:
- J/AJ/154/107
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The California-Kepler Survey (CKS) is an observational program developed to improve our knowledge of the properties of stars found to host transiting planets by NASA's Kepler Mission. The improvement stems from new high-resolution optical spectra obtained using HIRES at the W. M. Keck Observatory. The CKS stellar sample comprises 1305 stars classified as Kepler objects of interest, hosting a total of 2075 transiting planets. The primary sample is magnitude-limited (K_p_<14.2) and contains 960 stars with 1385 planets. The sample was extended to include some fainter stars that host multiple planets, ultra-short period planets, or habitable zone planets. The spectroscopic parameters were determined with two different codes, one based on template matching and the other on direct spectral synthesis using radiative transfer. We demonstrate a precision of 60K in T_eff_, 0.10dex in logg, 0.04dex in [Fe/H], and 1.0km/s in Vsini. In this paper, we describe the CKS project and present a uniform catalog of spectroscopic parameters. Subsequent papers in this series present catalogs of derived stellar properties such as mass, radius, and age; revised planet properties; and statistical explorations of the ensemble. CKS is the largest survey to determine the properties of Kepler stars using a uniform set of high-resolution, high signal-to-noise ratio spectra. The HIRES spectra are available to the community for independent analyses.
- ID:
- ivo://CDS.VizieR/J/MNRAS/437/3133
- Title:
- Candidate Neptunes around late-type dwarfs
- Short Name:
- J/MNRAS/437/3133
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Studies of transiting Neptune-size planets orbiting close to nearby bright stars can inform theories of planet formation because mass and radius and therefore mean density can be accurately estimated and compared with interior models. The distribution of such planets with stellar mass and orbital period relative to their Jovian-mass counterparts can test scenarios of orbital migration, and whether "hot" (period <10d) Neptunes evolved from "hot" Jupiters as a result of mass loss. We searched 1763 late K and early M dwarf stars for transiting Neptunes by analyzing photometry from the Wide Angle Search for Planets and obtaining high-precision (<=10^-3^) follow-up photometry of stars with candidate transit signals. We identified 92 candidate signals among 80 other stars and carried out 148 observations of predicted candidate transits with 1-2m telescopes.
- ID:
- ivo://CDS.VizieR/J/ApJ/770/90
- Title:
- Candidate planets in the habitable zones
- Short Name:
- J/ApJ/770/90
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- A key goal of the Kepler mission is the discovery of Earth-size transiting planets in "habitable zones" where stellar irradiance maintains a temperate climate on an Earth-like planet. Robust estimates of planet radius and irradiance require accurate stellar parameters, but most Kepler systems are faint, making spectroscopy difficult and prioritization of targets desirable. The parameters of 2035 host stars were estimated by Bayesian analysis and the probabilities p_HZ_ that 2738 candidate or confirmed planets orbit in the habitable zone were calculated. Dartmouth Stellar Evolution Program models were compared to photometry from the Kepler Input Catalog, priors for stellar mass, age, metallicity and distance, and planet transit duration. The analysis yielded probability density functions for calculating confidence intervals of planet radius and stellar irradiance, as well as p_HZ_. Sixty-two planets have p_HZ_>0.5 and a most probable stellar irradiance within habitable zone limits. Fourteen of these have radii less than twice the Earth; the objects most resembling Earth in terms of radius and irradiance are KOIs 2626.01 and 3010.01, which orbit late K/M-type dwarf stars. The fraction of Kepler dwarf stars with Earth-size planets in the habitable zone ({eta}_{Earth}_) is 0.46, with a 95% confidence interval of 0.31-0.64. Parallaxes from the Gaia mission will reduce uncertainties by more than a factor of five and permit definitive assignments of transiting planets to the habitable zones of Kepler stars.
- ID:
- ivo://CDS.VizieR/I/256
- Title:
- Carlsberg Meridian Catalogs
- Short Name:
- I/256
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This composite catalogue contains 180812 positions and magnitudes of 176591 stars north of declination -40deg, 155005 proper motions, and 25848 positions and magnitudes of 184 Solar System objects obtained with the Carlsberg Automatic Meridian Circle on La Palma during the period May 1984 to May 1998. It includes Carlsberg Meridian Catalogues Numbers 1 to 11 (CMC1-11); i.e. it comprises all the observations made since the instrument began operation on La Palma. The positions of the stars are for the epoch of observation and the equinox J2000.0, and are referred to the new International Celestial Reference Frame. The limiting magnitude is V=15.4. The catalogue mainly comprises positions and proper motions for the following programmes: 36000 International Reference Stars 30000 faint reference stars in a global net 18000 reference stars in the fields of radio sources 17000 stars in the Lick Northern Proper Motion catalogue 5000 reference stars for calibration of Schmidt plates 2600 stars in the Gliese catalogue of nearby stars 5000 stars in nearby OB associations 10500 F-type stars within 100 pc 9000 G-type dwarfs and giants, K-type giants stars within 300 pc 2200 unbiassed sample of K/M-type dwarf stars 19400 reference stars near Veron-Cetty galaxies 4700 variable stars (12-14 mag) in GCVS 12400 stars (11-14 mag) with pm>0".18/yr in NLTT and several smaller programmes mainly aimed at galactic kinematics. Positions and magnitudes of 12 novae and 8 supernovae which occurred in the years 1991 to 1998 are included. The catalogue also contains observations of the following Solar System objects: Callisto, Ganymede, Rhea, Titan, Iapetus, Hyperion, Uranus, Oberon, Neptune, Pluto and 173 minor planets and Comet P/Wild2. The mean error of a catalogue position in the zenith is 0".09 in right ascension and declination in CMC1-6, improving to 0".06 in CMC7-11. The accuracy in magnitude is 0.05 mag in CMC1-10, improving to 0.03 mag in CMC11. The mean error of the proper motions, derived by combining the position in this catalogue with those at earlier epochs, is typically in the range 0".003 to 0".004 per year. Cross-references are given to DM, AGK, SAO, HD and the double star catalogues ADS and WDS. The catalogue also contains 12216 mean annual observed positions of the FK5 stars used to transfer the instrumental system to the FK5 frame in the years 1984 to 1995. A compilation of all the meteorological data collected in the years 1984-1998, including the atmospheric extinction, is appended. This catalogue supersedes the previous versions which were numbered <I/126> (CMC1 and 2), <I/133> (CMC3), <I/147> (CMC4), <I/170> (CMC5), <I/189> (CMC6), <I/205> (CMC7) and <I/213> (CMC8).
- ID:
- ivo://CDS.VizieR/J/A+A/609/A117
- Title:
- CARMENES radial velocity curves of 7 M-dwarf
- Short Name:
- J/A+A/609/A117
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The main goal of the CARMENES survey is to find Earth-mass planets around nearby M-dwarf stars. Seven M-dwarfs included in the CARMENES sample had been observed before with HIRES and HARPS and either were reported to have one short period planetary companion (GJ 15 A, GJ 176, GJ 436, GJ 536 and GJ 1148) or are multiple planetary systems (GJ 581 and GJ 876). Aims. We aim to report new precise optical radial velocity measurements for these planet hosts and test the overall capabilities of CARMENES. We combined our CARMENES precise Doppler measurements with those available from HIRES and HARPS and derived new orbital parameters for the systems. Bona-fide single planet systems are fitted with a Keplerian model. The multiple planet systems were analyzed using a self-consistent dynamical model and their best fit orbits were tested for long-term stability. Results. We confirm or provide supportive arguments for planets around all the investigated stars except for GJ 15 A, for which we find that the post-discovery HIRES data and our CARMENES data do not show a signal at 11.4days. Although we cannot confirm the super-Earth planet GJ 15 Ab, we show evidence for a possible long-period (Pc=7025^+972^_-629_days) Saturn-mass (m_c_sini=51.8^+5.5^_-5.8_M_{Earth}_) planet around GJ 15 A. In addition, based on our CARMENES and HIRES data we discover a second planet around GJ 1148, for which we estimate a period Pc=532.6^+4.2^_-2.5_days, eccentricity e_c_=0.342^+0.050^_-0.062_ and minimum mass m_c_sini=68.1^+4.9^_-2.2_M_{Earth}_. The CARMENES optical radial velocities have similar precision and overall scatter when compared to the Doppler measurements conducted with HARPS and HIRES. We conclude that CARMENES is an instrument that is up to the challenge of discovering rocky planets around low-mass stars.
- ID:
- ivo://CDS.VizieR/J/AJ/151/59
- Title:
- Catalog of Earth-Like Exoplanet Survey Targets
- Short Name:
- J/AJ/151/59
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Locating planets in circumstellar habitable zones (HZs) is a priority for many exoplanet surveys. Space-based and ground-based surveys alike require robust toolsets to aid in target selection and mission planning. We present the Catalog of Earth-Like Exoplanet Survey Targets (CELESTA), a database of HZs around 37000 nearby stars. We calculated stellar parameters, including effective temperatures, masses, and radii, and we quantified the orbital distances and periods corresponding to the circumstellar HZs. We gauged the accuracy of our predictions by contrasting CELESTA's computed parameters to observational data. We ascertain a potential return on investment by computing the number of HZs probed for a given survey duration. A versatile framework for extending the functionality of CELESTA into the future enables ongoing comparisons to new observations, and recalculations when updates to HZ models, stellar temperatures, or parallax data become available. We expect to upgrade and expand CELESTA using data from the Gaia mission as the data become available.
