- ID:
- ivo://CDS.VizieR/J/A+A/656/A162
- Title:
- CARMENES stellar atmospheric parameters
- Short Name:
- J/A+A/656/A162
- Date:
- 22 Feb 2022
- Publisher:
- CDS
- Description:
- We determine effective temperatures, surface gravities, and metallicities for a sample of 343 M dwarfs observed with CARMENES, the double-channel, high-resolution spectrograph installed at the 3.5m telescope at Calar Alto Observatory. We employed SteParSyn, a Bayesian spectral synthesis implementation, along with a grid of synthetic spectra based on BT-Settl model atmospheres and the radiative transfer code turbospectrum. The synthetic grid was computed around 75 magnetically insensitive TiI and FeI along with the TiO gamma- and epsilon-bands. To avoid degeneracies in the parameter space, we imposed Bayesian priors based on multi-band photometric data available for the sample.
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- ID:
- ivo://CDS.VizieR/J/A+A/657/A87
- Title:
- CASCADES I. Sample definition and first results
- Short Name:
- J/A+A/657/A87
- Date:
- 22 Feb 2022
- Publisher:
- CDS
- Description:
- Following the first discovery of a planet orbiting a giant star in 2002, we started the CORALIE radial-velocity search for companions around evolved stars (CASCADES). We present the observations of three stars conducted at the 1.2m Leonard Euler Swiss telescope at La Silla Observatory, Chile, using the CORALIE spectrograph. We aim to detect planetary companions to intermediate-mass G- and K- type evolved stars and perform a statistical analysis of this population. We searched for new planetary systems around the stars HD22532 (TIC200851704), HD64121 (TIC264770836), and HD69123 (TIC146264536). We have followed a volume-limited sample of 641 red giants since 2006 to obtain high-precision radial-velocity measurements. We used the Data & Analysis Center for Exoplanets (DACE) platform to perform a radial-velocity analysis to search for periodic signals in the line profile and activity indices, to distinguish between planetary-induced radial-velocity variations and stellar photospheric jitter, and to search for significant signals in the radial-velocity time series to fit a corresponding Keplerian model. In this paper, we present the survey in detail, and we report on the discovery of the first three planets of the sample around the giant stars HD22532, HD64121, and HD69123.
- 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.
- ID:
- ivo://CDS.VizieR/J/AJ/161/189
- Title:
- Catalog of gyro-kinematic ages for ~30000 Kepler stars
- Short Name:
- J/AJ/161/189
- Date:
- 09 Mar 2022 22:00:00
- Publisher:
- CDS
- Description:
- Estimating stellar ages is important for advancing our understanding of stellar and exoplanet evolution and investigating the history of the Milky Way. However, ages for low-mass stars are hard to infer as they evolve slowly on the main sequence. In addition, empirical dating methods are difficult to calibrate for low-mass stars as they are faint. In this work, we calculate ages for Kepler F, G, and crucially K and M-dwarfs, using their rotation and kinematic properties. We apply the simple assumption that the velocity dispersion of stars increases over time and adopt an age-velocity-dispersion relation (AVR) to estimate average stellar ages for groupings of coeval stars. We calculate the vertical velocity dispersion of stars in bins of absolute magnitude, temperature, rotation period, and Rossby number and then convert velocity dispersion to kinematic age via an AVR. Using this method, we estimate gyro-kinematic ages for 29949 Kepler stars with measured rotation periods. We are able to estimate ages for clusters and asteroseismic stars with an rms of 1.22Gyr and 0.26Gyr respectively. With our Astraea machine-learning algorithm, which predicts rotation periods, we suggest a new selection criterion (a weight of 0.15) to increase the size of the McQuillan et al. catalog of Kepler rotation periods by up to 25%. Using predicted rotation periods, we estimated gyro-kinematic ages for stars without measured rotation periods and found promising results by comparing 12 detailed age-element abundance trends with literature values.
- ID:
- ivo://CDS.VizieR/J/A+A/600/A50
- Title:
- Catalog of hot subdwarf stars
- Short Name:
- J/A+A/600/A50
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- In preparation for the upcoming all-sky data releases of the Gaia mission we compiled a catalog of known hot subdwarf stars and candidates drawn from the literature and yet unpublished databases. By matching this catalog with astrometric and photometric data from the Gaia mission, we will develop selection criteria to construct a homogeneous, magnitude-limited all-sky catalog of hot subdwarf stars based on Gaia data.
- ID:
- ivo://CDS.VizieR/J/ApJS/232/26
- Title:
- Catalog of Kepler flare stars
- Short Name:
- J/ApJS/232/26
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We aim to perform a statistical study of stellar flares observed by Kepler. We want to study the flare amplitude, duration, energy, and occurrence rates, and how they are related to the spectral type and rotation period. To that end, we have developed an automated flare detection and characterization algorithm. We have harvested the stellar parameters from the Kepler input catalog and the rotation periods from McQuillan et al. (2014, Cat. J/ApJS/211/24). We find several new candidate A stars showing flaring activity. Moreover, we find 653 giants with flares. From the statistical distribution of flare properties, we find that the flare amplitude distribution has a similar behavior between F+G types and K+M types. The flare duration and flare energy seem to be grouped between G+K+M types versus F types and giants. We also detect a tail of stars with high flare occurrence rates across all spectral types (but most prominent in the late spectral types), and this is compatible with the existence of "flare stars." Finally, we have found a strong correlation of the flare occurrence rate and the flare amplitude with the stellar rotation period: a quickly rotating star is more likely to flare often and has a higher chance of generating large flares.
- ID:
- ivo://CDS.VizieR/J/AJ/153/95
- Title:
- Catalog of Suspected Nearby Young Stars
- Short Name:
- J/AJ/153/95
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a new nearby young moving group (NYMG) kinematic membership analysis code, LocAting Constituent mEmbers In Nearby Groups (LACEwING), a new Catalog of Suspected Nearby Young Stars, a new list of bona fide members of moving groups, and a kinematic traceback code. LACEwING is a convergence-style algorithm with carefully vetted membership statistics based on a large numerical simulation of the Solar Neighborhood. Given spatial and kinematic information on stars, LACEwING calculates membership probabilities in 13 NYMGs and three open clusters within 100 pc. In addition to describing the inputs, methods, and products of the code, we provide comparisons of LACEwING to other popular kinematic moving group membership identification codes. As a proof of concept, we use LACEwING to reconsider the membership of 930 stellar systems in the Solar Neighborhood (within 100 pc) that have reported measurable lithium equivalent widths. We quantify the evidence in support of a population of young stars not attached to any NYMGs, which is a possible sign of new as-yet-undiscovered groups or of a field population of young stars.
- ID:
- ivo://CDS.VizieR/J/MNRAS/480/2953
- Title:
- Catalogue of CP stars (HgMn, ApBp, AmFm)
- Short Name:
- J/MNRAS/480/2953
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- In this paper, we present a new catalogue of chemically peculiar (CP) stars obtained by compiling publications in which abundances of metals are provided. Our catalogue includes 428 stars for which the data were obtained through spectroscopic observations. Most of them (416) are AmFm, HgMn, and ApBp stars. We have used this compilation to proceed to a statistical overview of the abundance anomalies versus the physical parameters of the stars. Spearman's rank correlation test has been applied, and a significant number of correlations of abundance peculiarities with respect to effective temperature, surface gravity, and rotation velocity have been found. Four interesting cases are discussed in details: the Mn peculiarities in HgMn stars, the Ca correlation with respect to effective temperature in AmFm stars, the case of helium and iron in ApBp stars. Furthermore, we checked for ApBp stars using Anderson-Darling test whether the belonging to a multiple system is a determinant parameter or not for abundance peculiarities.
- ID:
- ivo://CDS.VizieR/III/200B
- Title:
- Catalogue of [Fe/H]
- Short Name:
- III/200B
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The catalogue includes [Fe/H] determinations and atmospheric parameters (Teff, logg ) obtained from high resolution spectroscopic observations and detailed analyses, most of them carried out with the help of model-atmospheres. This fifth Edition of the catalogue contains 5946 determinations for 3247 stars, including 751 stars in 84 associations, clusters or galaxies. The literature (700 bibliographical references) is complete up to December 1995. The Catalogue is made up of three tables : Table 1 : field stars Table 2 : stars in galactic associations and clusters, and in SMC, LMC, M33 Table 3 : numbered list of bibliographical references
- ID:
- ivo://CDS.VizieR/III/221A
- Title:
- Catalogue of [Fe/H] of F, G, K stars
- Short Name:
- III/221A
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The catalogue presented here is a compilation of published atmospheric parameters (Teff, logg, [Fe/H]) obtained from high resolution, high signal-to-noise spectroscopic observations. This new edition has changed compared to the five previous versions. It is now restricted to intermediate and low-mass stars (F, G, and K stars). It contains 6354 determinations of (Teff, logg, [Fe/H]) for 3356 stars, including 899 stars in 79 stellar systems. The literature is complete between January 1980 and December 2000 and includes 378 references. The catalogue is made up of two tables, one for field stars and one for stars in galactic associations, open and globular clusters and external galaxies.
