Садржај
Слике
Уплоадјуј своје слике
DSS Images Other Images
Везани чланци
VSOP: the variable star one-shot project. I. Project presentation and first data release
Context: About 500 new variable stars enter the General Catalogue ofVariable Stars (GCVS) every year. Most of them however lackspectroscopic observations, which remains critical for a correctassignement of the variability type and for the understanding of theobject. Aims: The Variable Star One-shot Project (VSOP) is aimed at (1)providing the variability type and spectral type of all unstudiedvariable stars, (2) process, publish, and make the data available asautomatically as possible, and (3) generate serendipitous discoveries.This first paper describes the project itself, the acquisition of thedata, the dataflow, the spectroscopic analysis and the on-lineavailability of the fully calibrated and reduced data. We also presentthe results on the 221 stars observed during the first semester of theproject. Methods: We used the high-resolution echelle spectrographsHARPS and FEROS in the ESO La Silla Observatory (Chile) to survey knownvariable stars. Once reduced by the dedicated pipelines, the radialvelocities are determined from cross correlation with synthetic templatespectra, and the spectral types are determined by an automatic minimumdistance matching to synthetic spectra, with traditional manual spectraltyping cross-checks. The variability types are determined by manuallyevaluating the available light curves and the spectroscopy. In thefuture, a new automatic classifier, currently being developed by membersof the VSOP team, based on these spectroscopic data and on thephotometric classifier developed for the COROT and Gaia space missions,will be used. Results: We confirm or revise spectral types of 221variable stars from the GCVS. We identify 26 previously unknown multiplesystems, among them several visual binaries with spectroscopic binaryindividual components. We present new individual results for themultiple systems V349 Vel and BCGru, for the composite spectrum star V4385Sgr, for the T Tauri star V1045 Sco, andfor DM Boo which we re-classify as a BY Draconisvariable. The complete data release can be accessed via the VSOP website.Based on data obtained at the La Silla Observatory, European SouthernObservatory, under program ID 077.D-0085.
| Observations of OB-stars at the former Leiden Southern Station
About 700 stars, mostly OB-stars, were observed by the author at theformer Leiden Southern Station at Hartebeespoortdam, South Africa, inthe observing seasons 1965, 1968, 1969, 1974, 1977, 1978. Observationswere made in the five channels of the Walraven photometric system. Dueto weathering of the telescope mirror the W channel gave no reliableresults for the faintest stars (m = 11 mag); in these cases the U-Wcolour index is not given. The change in sensitivity in the V channel,supposedly having occurred in 1968, was not recognised. Table~5 is onlyavailable 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/qcat?J/A+A/369/527
| The 74th Special Name-list of Variable Stars
We present the Name-list introducing GCVS names for 3153 variable starsdiscovered by the Hipparcos mission.
| Walraven photometry of nearby southern OB associations
Homogeneous Walraven (VBLUW) photometry is presented for 5260 stars inthe regions of five nearby southern OB associations: Scorpio Centaurus(Sco OB2), Orion OB1, Canis Major OB1, Monoceros OB1, and Scutum OB2.Derived V and (B - V) in the Johnson system are included.
| Radial velocities for early type stars in six galactic regions
Coudespectroscopy has been carried out for 353 stars of spectral typesB0-A0 and V magnitudes between 6.5 and 10.8 m, selected in six regions(three northern and three southern) close to the galactic plane at thegalactic longitudes 135, 175, 315 and 350 deg. The radial velocitieswere obtained by cross-correlating each spectrogram with a referencespectrogram giving an internal error of 1.4 km/s.
| Four-colour and H-beta photometry for early type stars in three southern galactic regions
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1980A&AS...41...85L&db_key=AST
| Ultraviolet television data from the orbiting astronomical observatory. II - Stellar ultraviolet colors and interstellar extinction
The results from the Celescope Catalog of Ultraviolet StellarObservations (Davis, Deutschman, and Haramundanis 1973) are studied,emphasizing statistical groups and subgroups of stars. In spite of therather large observational errors, the great number of Celescopeobservations make it possible to do that kind of study with reasonableaccuracy. Some stars have ultraviolet colors that differ significantlyfrom those of the group to which they have been assigned on the basis ofground-based observations. An attempt is made to describe the generalproperties of the ultraviolet colors of the stars as observed by theCelescope experiment on board NASA's Orbiting Astronomical Observatory(OAO-2). Besides the direct applicability of these results to thegeneral study of stellar atmospheres and of interstellar extinction,they are also considered as a frame of reference for further studies ofindividual stars and groups of stars.
| Studies of the Milky Way from Centaurus to Norma. III. OB stars.
Not Available
|
Додај нови чланак
Линкови у сродству са темом
Додај нови линк
Чланови следећих група \:
|
Посматрања и Астрометриски подаци
| Сазвежђа: | Кентаур |
| Ректацензија: | 14h19m09.05s |
| Deклинација: | -55°52'56.1" |
| Apparent магнитуда: | 7.298 |
| Даљина: | 645.161 parsecs |
| Proper motion RA: | -8.7 |
| Proper motion Dec: | -7.1 |
| B-T magnitude: | 7.39 |
| V-T magnitude: | 7.306 |
Каталог и designations:
|
