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Pulkovo compilation of radial velocities for 35495 stars in a common system.
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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
| Discovery of two short-period eclipsing binaries with active components.
We present high-precision UBV(RI)_c_ photometry as well as soft X-raylight curves for the visual triple system HD 9770 and the visual binaryHD 195434, obtained at the European Southern Observatory and extractedfrom the ROSAT all-sky survey, respectively. The optical photometryrevealed that in both systems one component is a very short-periodeclipsing binary showing also BY Dra-type variability. We have computedaccurate orbital periods, deduced approximate physical parameters,spectral classifications, distances and X-ray luminosities andidentified which component of each visual system is responsible for theoptical variability. Futhermore, we find that both systems are variablein X-rays, but no correlation with the optical variability is seen.
| Photometry of cool stars detected in extreme-ultraviolet (EUV) all-sky surveys.
We present high-precision UBV(RI)_c_ photometry for a small sample ofcool stars detected at EUV wavelengths by the ROSAT WFC and/or the EUVEall-sky survey. Four out of the five stars observed are variable and oneof them is an eclipsing binary. Amplitudes up to 0.38 magnitudes in theV band have been observed and clear colour variations have been found.We have computed the photometric periods and deduced approximatespectral classifications and distances.
| A catalog of K giants at the South Galactic Pole - Broadband and DDO photometry and radial velocities
We describe a sample of K giants at the South Galactic Pole, selected toexamine the chemical and kinematical properties of stars perpendicularto the galactic plane and to measure the local column density of thedisk. We report velocities, abundances, absolute magnitudes, andbroadband BV photometry for over 500 giants.
| Local dark matter from a carefully selected sample
The precise data obtained by Flynn and Freeman (1991) on K giants at thesouth Galactic pole are used to analyze the amount of local dark matterin which the systematic effects can be modeled easily and evaluatedaccurately. The method of Bahcall (1984) is employed to solve theself-consistent equations for the distribution of dark matter. TheK-giant survey is found to provide significant evidence for disk darkmatter. Taking into account all recognized sources of error using astatistical test devised by Gould (1989, 1990), a model with no darkmatter is inconsistent with the data at the 86-percent confidence level.The best-fit P-model (in which dark matter is distributed proportionallyto known matter) has 53 percent more dark matter than visible matter.
| Hyades and Sirius supercluster members brighter than magnitude(V) 7.1. I - The first six hours of right ascension
This is the first of four papers listing the probable members of theHyades and Sirius superclusters among stars brighter than V = 7.1 mag.The star sample is contained in the Bright Star Catalogue and itsSupplement, augmented with a further supplement of 550 stars foundduring various observing programs over the past 40 years. Accurate,four-color and H-beta, or (RI), photometry is available for most of thesupercluster members. The criteria for membership are the comparisons ofthe proper motion, radial velocity, and luminosity obtained from thesupercluster parameters with the observed motions and the luminosityderived from the photometric parameters. New proper motions, based onall available catalogs, have been derived for the additional 550 starsdiscussed here, as well as for all supercluster members.
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Membre dels grups següents:
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Dades d'Observació i Astrometria
| Constel·lació: | Sculptor |
| Ascensió Recta: | 01h39m21.54s |
| Declinació: | -33°33'53.2" |
| Magnitud Aparent: | 6.557 |
| Distancia: | 145.773 parsecs |
| Moviment propi RA: | 5 |
| Moviment propi Dec: | -0.7 |
| B-T magnitude: | 8.041 |
| V-T magnitude: | 6.68 |
Catàlegs i designacions:
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