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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
| A comparative study of NA I and CA II infrared lines in stars, star clusters and galaxy nuclei - an alternative to the dwarf-enriched population
A comparative study is made of the near-infrared Na I doublet and the CaII triplet, among sets of stars, star clusters and galaxy nuclei. Inparticular, the semistellar nucleus of M31 is studied. Evidence is foundthat the enhancement of the absorption feature around 8200 A in galaxynuclei is not due to a strengthening of the Na I lines, but rather toanother absorber, possibly a molecular band at about 8205 A which variesstrongly with Theta(eff) and metallicity. Therefore, an alternativeexplanation to the classical discussion about dwarf/giant star contentin M31, is that of an increased metallicity in the semistellar nucleusof M31, with respect to its bulge or to the nucleus of M32. A similarresult is found from molecular bands in the visible part of thespectrum, like CN and C2 which show highly nonlinear dependences on themetallicity.
| Radial velocities of southern stars obtained with the photoelectric scanner CORAVEL. III - 790 late-type bright stars
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1985A&AS...59...15A&db_key=AST
| RS Gru : a dwarf cepheid in a binary system.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1978MNRAS.184....1B&db_key=AST
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Osservazione e dati astrometrici
| Costellazione: | Indiano |
| Ascensione retta: | 21h45m19.00s |
| Declinazione: | -49°29'55.0" |
| Magnitudine apparente: | 6.45 |
| Distanza: | 127.877 parsec |
| Moto proprio RA: | 72.9 |
| Moto proprio Dec: | 48 |
| B-T magnitude: | 7.952 |
| V-T magnitude: | 6.591 |
Cataloghi e designazioni:
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INHABITED SKY
