Садржај
Слике
Уплоадјуј своје слике
DSS Images Other Images
Везани чланци
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
| SANTIAGO 91, a right ascension catalogue of 3387 stars (equinox J2000).
The positions in right ascension of 3387 stars belonging to the Santiago67 Catalogue, observed with the Repsold Meridian Circle at Cerro Calan,National Astronomical Observatory, during the period 1989 to 1994, aregiven. The average mean square error of a position, for the wholeCatalogue, is +/-0.009 s. The mean epoch of the catalogue is 1991.84.
| Axial rotation of BY Dra-type stars and related objects
Periods of the rotational modulation of the brightness of BY Dra-typestars, Pleiades spotted stars, 'naked' T Tau stars, and T Tau-type starsare compared with absolute bolometric stellar magnitudes. It is arguedthat most BY Dra stars have an age of 10 exp 8 yr, and very fast andrelatively slowly rotating objects are encountered among them.
| UBVRI photometry of FKSZ stars. II
The results of UBVRI photometry for 169 stars of the Faint FundamentalStars Catalog (Zverev, 1957) in the declination zone lambda of between-30 and -60 deg are presented. Observations were obtained between May1984 and February 1987 using the 50-cm ESO telescope at La Silla.Tabular data presented include the number of the star in the E-regions,the V magnitude, the (B-V), (U-B), (V-R), and (R-I) colors, and thespectral types.
| Anomalous distribution of axial inclinations of T Tauri stars
Axial inclinations and their associated errors are derived for 20 TTauri stars. The distribution of these inclinations is shown to besignificantly different than that expected if the inclinations weredistributed at random. A suggestion for current observing programs ismade.
| Distribution of B5 to A5 stars at (l, b) = (253 deg, -7 deg)
A study to V of about 12 mag is conducted for the distribution ofinterstellar extinction and early type stars (up to A5) in the (l, b) =(253 deg, -7 deg) field. The space density of B5, B8-A0, and A2-A5 starsis found to be normal for a field outside the galactic plane, and thestellar and extinction data indicate that the direction in question liesout of the matter plane of the Milky Way at least to 3 kpc. The higherextinction of Bochun 15 and the absence of background galaxies, however,suggest the possible presence of the galactic warp at -7 deg, atdistances beyond about 5 kpc, as well as a total higher extinction thanthe maximum of E(B-V) = 0.53 for d greater than 10 kpc, as found at (l,b) = (245 deg, zero deg).
|
Додај нови чланак
Линкови у сродству са темом
Додај нови линк
Чланови следећих група \:
|
Посматрања и Астрометриски подаци
| Сазвежђа: | Крма |
| Ректацензија: | 07h31m02.03s |
| Deклинација: | -34°59'03.1" |
| Apparent магнитуда: | 7.492 |
| Даљина: | 3030.303 parsecs |
| Proper motion RA: | -0.1 |
| Proper motion Dec: | 3.1 |
| B-T magnitude: | 9.738 |
| V-T magnitude: | 7.678 |
Каталог и designations:
|
INHABITED SKY
