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מאמרים קשורים
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
| On the Photometric Variability of Red Clump Giants
Hipparcos photometry of the 308 red clump giants identified by Paczynskiet al. (1999) is investigated. These stars are found to be quite stableduring the three years of observation, but questions remain about longerterm stability.
| 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
| The ROSAT all-sky survey catalogue of optically bright late-type giants and supergiants
We present X-ray data for all late-type (A, F, G, K, M) giants andsupergiants (luminosity classes I to III-IV) listed in the Bright StarCatalogue that have been detected in the ROSAT all-sky survey.Altogether, our catalogue contains 450 entries of X-ray emitting evolvedlate-type stars, which corresponds to an average detection rate of about11.7 percent. The selection of the sample stars, the data analysis, thecriteria for an accepted match between star and X-ray source, and thedetermination of X-ray fluxes are described. Catalogue only available atCDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or viahttp://cdsweb.u-strasbg.fr/Abstract.html
| The Southern Vilnius Photometric System. IV - The E region standard stars
This paper is the fourth in a series on the extension of the Vilniusphotometric system to the Southern Hemisphere. Observations were made of60 stars in the Harvard Standard E regions to increase a set of standardstars.
| Accurate Positions Of Suspected Variable Stars Near The South Galactic Pole
Not Available
| Secondary UVBY standards in the Harvard E-regions
Photoelectric uvby photometry for 201 stars which are already UBV (RI)cstandards is presented. The photoelectric data are closely tied to theCousins uvby standards and the stars should be suitable for use asfainter (7-11 mag) secondary standards.
| Secondary standards for H-beta photometry in the Southern Hemisphere (second series).
Not Available
| UBV (RI)c standard stars in the E- and F-regions and in the Magellanic Clouds - a revised catalogue.
Not Available
| Secondary standards for the Stromgren UVBY system
Observations of 158 E region stars have been made in the Stromgrensystem, using the 46-cm reflector at Cape Town. They are mostly brighterthan eighth magnitude and are intended for use as secondary standardsfor the four-color system. The E region relative zero points are definedwith a precision of + or - 0.001 mag, and the internal standard errorsof the colors life between + or - 0.001 and + or - 0.002 mag.
| Stellar kinematics and the stability of disks in spiral galaxies
The velocity dispersion of the old disk population in two spiralgalaxies is observed, noting that the radial decline of theSc-spiral-NGC 5247 vertical velocity dispersion ranges from the centerto about two scale lengths. This is in agreement with predictions madefor a disk of constant thickness and M/L ratio. The (M/L)B value for theold disk is 6 + or - 2 solar units from five galaxies. A parameter forstability against barlike modes (proposed by Efstathiou et al., 1982) isestimated for systems with mesured rotational velocity an disk scalelength. The asymmetric shift and absorption line profile widths aremeasured for the Sb spiral NGC 7184, and it is found that the radialvelocity dispersion also decreases with the radius. The proposedsolution has Tomre's Q rising from 1.7 to 2.2 between 0.9 and 2 scalelengths. It is noted that in the inner regions, the velocity dispersioncontributes significantly to the global disk stability.
| Abundances in field dwarf stars. I - Atmospheric parameters
Atmospheric parameters have been determined for a sample of 116 fielddwarf stars, plus 10 faint field giants and three Hyades dwarfs.Effective temperatures were found from new R-I photometry, plus R-I,b-y, and V-K colors and some spectrophotometric scans from theliterature. Surface gravities and metallicities were derived fromStromgren photometry from the literature and intermediate dispersionspectra. Empirical spectral indices and the Stromgren photometry werecalibrated using results of published high dispersion abundanceanalyses, supplemented with gravities based on parallax data andestimated masses. Stromgren c(1) and m(1) indices were found to remainuseful for G-type stars. Estimated random errors in the final parametersfor an individual star are + or - 70 K in T(eff), + or - 0.15 in log g,and + or - 0.10 in Fe/H.
| Abundances in field dwarf stars. II - Carbon and nitrogen abundances
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1985ApJ...289..556L&db_key=AST
| Photometric standard stars for the UBV and (RI)KC systems.
Not Available
| VRI standards in the E regions
Not Available
| Standard Stars for VRI Photometry with S25 Response Photocathodes [Errata: 1974MNSSA..33....1C]
Not Available
| Standard magnitudes in the E regions.
Not Available
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לינקים קשורים
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משמש של הקבוצה הבאה
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תצפית ומידע אסטרומטרי
| קבוצת-כוכבים: | עגור |
| התרוממות ימנית: | 22h42m43.10s |
| סירוב: | -44°14'52.0" |
| גודל גלוי: | 6.07 |
| מרחק: | 98.135 פארסק |
| תנועה נכונה: | 34.3 |
| תנועה נכונה: | 36 |
| B-T magnitude: | 7.3 |
| V-T magnitude: | 6.175 |
קטלוגים וכינוים:
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INHABITED SKY
