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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
| 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.
| Colours Line Strengths and Stellar Kinematics of NGC2663 and NGC5018
Results of the analysis of broad-band optical images and long-slitspectra of the two elliptical galaxies NGC 2663 and 5018 are presented.Line-strength profiles of Mg_2_, Fe_5270_ and Fe_5335_ have been derivedfor both galaxies, together with rotational velocity and velocitydispersion curves at three and four position angles (PAs) for NGC 2663and 5018, respectively. The measurements extend to about 1.8 effectiveradii for NGC 2663, and to about 3 effective radii for NGC 5018.Axisymmetric dynamical models with distribution function f= f(E, J_z_)(i.e. depending only on the energy E and the angular momentum along thesymmetry axis J_z_) have been fitted to the kinematic profiles of bothgalaxies, to derive information about the intrinsic shapes of theluminous galaxies and the sizes and shapes of possible dark haloes. Inagreement with what has been found for other ellipticals: (i) versus Mg_2_ shows, within both galaxies, a steeper slope than thatshown by galactic nuclei, and (ii) the slope is approximately equal inthe two galaxies and constant within each galaxy (over the whole radialrange, to ~2R_e_). A shift is observed between the two galaxies,implying different [Mg/Fe] abundance ratios. In NGC 2663, the derived[Mg/Fe] abundance ratio is (as is normally found in ellipticals) largerthan solar; its colour [d(B - R )/d log r = - 0.08] and Mg_2_ (dMg_2_/dlog r = - 0.06) gradients are consistent with each other and with achange in metallicity only. The galaxy shows a hint of counter-rotationwithin the innermost 20 arcsec and minor axis rotation. Any oblate orprolate model fitting its kinematics along any two position angles failsto fit the third position angle available, the discrepancy with the databeing a systematic shift. Most probably, this galaxy is a triaxialobject (observed V_rot_/σ~ 0.15 with e~0.3, anisotropy parameterδ >= 0.2-0.3); alternatively, it might be prolate but alwayswith an anisotropic velocity dispersion tensor. In NGC 5018, an almostflat velocity dispersion profile is observed out to the last measuredpoint. Assuming that the galaxy is an axisymmetric rotator, such a flata profile can be reproduced at a confidence level >~ 5 sigma only ifa very massive dark matter halo surrounds the luminous component (M_D_ ~6 M_lum_). A rather strong (B-R) colour gradient is observed in NGC 5018[d(B- R)/dlog r= -0.13], despite its shallow Mg_2_ gradient (dMg_2_/dlogr= - 0.04). Although the whole galaxy is blue, its central (B - R)colour and the observed patchy structure in the (B - R) colour mapsuggest a considerable amount of extinction in its central regions. Ifthe dust follows the Galactic extinction law, at 1550 A one could evenexpect ~2 mag of extinction. This might hide a younger stellarpopulation diluting the Mg_2_ line strength, and might explain the lackof UV flux reported by other authors. The dilution of Mg_2_ would alsoexplain the solar [Mg/Fe] abundance ratio.
| Long-term photometry of variables at ESO. I - The first data catalogue (1982-1986)
This paper presents the catalog of photometric data in the Stromgrensystem obtained during the first four years (October 1982 - September1986) of the Long-Term Photometry of Variables (LTPV) program at ESO.The data are available in computer-readable form.
| Large and Kinematically Unbiased Samples of G- and K-Type Stars. III. Evolved Young Disk Stars in the Bright Star Sample
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1989PASP..101...54E&db_key=AST
| 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.
| Investigation of a Milky Way field in Canis Major
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1974AJ.....79.1022C&db_key=AST
| Catalog of Indidual Radial Velocities, 0h-12h, Measured by Astronomers of the Mount Wilson Observatory
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1970ApJS...19..387A&db_key=AST
| Narrow-Band and Broad-Band Photometry of Red Stars. III. Southern Giants
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1970ApJ...161..199E&db_key=AST
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Besorolás csoportokba:
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Pozíciós és asztrometriai adatok
| Csillagkép: | Egyszarvú |
| Rektaszcenzió: | 07h14m15.50s |
| Deklináció: | -09°56'51.0" |
| Vizuális fényesség: | 5.9 |
| Távolság: | 719.424 parszek |
| RA sajátmozgás: | -5.5 |
| Dec sajátmozgás: | 3.3 |
| B-T magnitude: | 7.91 |
| V-T magnitude: | 6.066 |
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INHABITED SKY
