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A catalog of bright calibrator stars for 200-m baseline near-infrared stellar interferometry
We present in this paper a catalog of reference stars suitable forcalibrating infrared interferometric observations. In the K band,visibilities can be calibrated with a precision of 1% on baselines up to200 meters for the whole sky, and up to 300 meters for some part of thesky. This work, extending to longer baselines a previous catalogcompiled by Bordé et al. (2002, A&A, 393, 183), isparticularl y well adapted to hectometric-class interferometers such asthe Very Large Telescope Interferometer (VLTI, Glindemann et al. 2003,Proc. SPIE, 4838, 89) or the CHARA array (ten Brummelaar et al. 2003,Proc. SPIE, 4838, 69) when one is observing well-resolved, high-surfacebrightness objects (K 8). We use the absolute spectro-photometriccalibration method introduced by Cohen et al. (1999, AJ, 117, 1864) toderive the angular diameters of our new set of 948 G8-M0 calibratorstars extracted from the IRAS, 2MASS and MSX catalogs. Angular stellardiameters range from 0.6 mas to 1.8 mas (median is 1.1 mas) with amedian precision of 1.35%. For both the northern and southernhemispheres, the closest calibrator star is always less than 10°away.
| CHARM2: An updated Catalog of High Angular Resolution Measurements
We present an update of the Catalog of High Angular ResolutionMeasurements (CHARM, Richichi & Percheron \cite{CHARM}, A&A,386, 492), which includes results available until July 2004. CHARM2 is acompilation of direct measurements by high angular resolution methods,as well as indirect estimates of stellar diameters. Its main goal is toprovide a reference list of sources which can be used for calibrationand verification observations with long-baseline optical and near-IRinterferometers. Single and binary stars are included, as are complexobjects from circumstellar shells to extragalactic sources. The presentupdate provides an increase of almost a factor of two over the previousedition. Additionally, it includes several corrections and improvements,as well as a cross-check with the valuable public release observationsof the ESO Very Large Telescope Interferometer (VLTI). A total of 8231entries for 3238 unique sources are now present in CHARM2. Thisrepresents an increase of a factor of 3.4 and 2.0, respectively, overthe contents of the previous version of CHARM.The catalog is only available in electronic form at the CDS viaanonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or via http://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/431/773
| Catalogue of Apparent Diameters and Absolute Radii of Stars (CADARS) - Third edition - Comments and statistics
The Catalogue, available at the Centre de Données Stellaires deStrasbourg, consists of 13 573 records concerning the results obtainedfrom different methods for 7778 stars, reported in the literature. Thefollowing data are listed for each star: identifications, apparentmagnitude, spectral type, apparent diameter in arcsec, absolute radiusin solar units, method of determination, reference, remarks. Commentsand statistics obtained from CADARS are given. The Catalogue isavailable in electronic form at the CDS via anonymous ftp tocdsarc.u-strasbg.fr (130.79.128.5) or viahttp://cdsweb.u-strasbg.fr/cgi-bin/qcar?J/A+A/367/521
| Intrinsic Energy Distribution in Stellar Spectra in the Wavelength Interval 320--760 NM
The intrinsic energy distributions in the interval 320--760 nm ofspectral types B5--G8 of luminosity V, F0--F5 of luminosity IV andG8--M2 of luminosity III, determined by authors, are intercompared withthe catalogue of the mean energy distribution data published bySviderskiene (1988).
| Vitesses radiales. Catalogue WEB: Wilson Evans Batten. Subtittle: Radial velocities: The Wilson-Evans-Batten catalogue.
We give a common version of the two catalogues of Mean Radial Velocitiesby Wilson (1963) and Evans (1978) to which we have added the catalogueof spectroscopic binary systems (Batten et al. 1989). For each star,when possible, we give: 1) an acronym to enter SIMBAD (Set ofIdentifications Measurements and Bibliography for Astronomical Data) ofthe CDS (Centre de Donnees Astronomiques de Strasbourg). 2) the numberHIC of the HIPPARCOS catalogue (Turon 1992). 3) the CCDM number(Catalogue des Composantes des etoiles Doubles et Multiples) byDommanget & Nys (1994). For the cluster stars, a precise study hasbeen done, on the identificator numbers. Numerous remarks point out theproblems we have had to deal with.
| Evolved GK stars near the sun. I - The old disk population
A sample of nearly two thousand GK giants with intermediate band, (R,I),DDO and Geneva photometry has been assembled. Astrometric data is alsoavailable for most of the stars. The some 800 members of the old diskpopulation in the sample yield accurate luminosities (from two sources),reddening values and chemical abundances from calibrations of thephotometric parameters. Less than one percent of the objects arepeculiar in the sense that the flux distribution is abnormal. Thepeculiarity is signaled by strong CH (and Ba II) and weak CH. The CH+stars are all spectroscopic binaries, probably with white dwarfcompanions, whereas the CH- stars are not. A broad absorption band,centered near 3500 A, is found in the CH+ stars whereas the CH- objectshave a broad emission feature in the same region. The intensity of theseabsorptions and emissions are independent of the intensity of abnormalspectral features. Ten percent of the old disk sample have a heavyelement abundance from one and a half to three times the solar value.The distribution of the heavy element abundances is nearly a normal onewith a peak near solar abundance and ranges three times to one sixthsolar. The distribution of the (U, V) velocities is independent of theheavy element abundance and does not appear to be random. Ten percent ofthe old disk stars show a CN anomaly, equally divided between CN strongand CN weak. Several stars of individual astrometric or astrophysicalimportance are isolated.
| Einstein Observatory magnitude-limited X-ray survey of late-type giant and supergiant stars
Results are presented of an extensive X-ray survey of 380 giant andsupergiant stars of spectral types from F to M, carried out with theEinstein Observatory. It was found that the observed F giants orsubgiants (slightly evolved stars with a mass M less than about 2 solarmasses) are X-ray emitters at the same level of main-sequence stars ofsimilar spectral type. The G giants show a range of emissions more than3 orders of magnitude wide; some single G giants exist with X-rayluminosities comparable to RS CVn systems, while some nearby large Ggiants have upper limits on the X-ray emission below typical solarvalues. The K giants have an observed X-ray emission level significantlylower than F and F giants. None of the 29 M giants were detected, exceptfor one spectroscopic binary.
| Large and kinematically unbiased samples of G- and K-type stars. IV - Evolved stars of the old disk population
Modified Stromgren and (R,I) photometry, along with DDO and Genevaphotometry, are presented for a complete sample of evolved old-disk Gand K giants in the Bright Star Catalogue. Stars with ages of between1.5 x 10 to the 9th and 10 to the 10th yr are found to have anear-normal distribution of heavy element abundances, centered on anFe/H abundance ratio of -0.1 dex. The old disk clusters NGC 3680 and IC4651 contain red-straggler young-disk giants that are probablycontemporaries of the blue stragglers in the clusters.
| Large and kinematically unbiased samples of G- and K-type stars. II - Observations of evolved stars in the Bright Star sample. III - Evolved young disk stars in the Bright Star sample
Four color and RI observations were obtained for a large sample ofG-type and K-type stars in the Bright Star Catalogue. Data are firstpresented for 110 evolved stars. Photometry of evolved young diskpopulation stars have then been calibrated for luminosity, reddening,and metallicity on the basis of results for members of the Hyades andSirius superclusters. New DDO results are given for 120 stars.
| Population studies. II - Kinematics as a function of abundance and galactocentric position for (Fe/H) of -0.6 or less
A catalog is presented of some 1200 Galactic objects which have radialvelocities and (Fe/H) abundances of -0.6 or less. These data areanalyzed to yield information on the kinematic properties of the olderpopulations of the Galaxy and on the interdependence between kinematicsand abundance. It is found that the kinematics of the availablekinematically selected stars differ from those of the nonkinematicallyselected objects. No evidence is found for any significant difference inthe kinematic properties of the various halo subgroups, nor for anydependence of kinematics on abundance. While the rotation of the halo issmall at about 37 km/s for (Fe/H) of -1.2 or less, it rises quickly forhigher abundances to a value of about 160 km/s at (Fe/H) = 0.6. Objectsin the abundance range -0.9 to -0.6 appear to belong predominantly to apopulation possessing the kinematic characteristics of a thick disk. Theimplications of these findings for the suggestion that globular clustersbelong to the same population as the noncluster objects, for the originof the thick disk, and for the mass of the Galaxy are discussed.
| UVBY BET photometry of equatorial and southern bright stars.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1977A&AS...27...47H&db_key=AST
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Pozíciós és asztrometriai adatok
| Csillagkép: | Eridánusz |
| Rektaszcenzió: | 02h53m35.30s |
| Deklináció: | -22°22'35.0" |
| Vizuális fényesség: | 5.95 |
| Távolság: | 93.197 parszek |
| RA sajátmozgás: | 85.6 |
| Dec sajátmozgás: | -78 |
| B-T magnitude: | 7.252 |
| V-T magnitude: | 6.046 |
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