Intermediate-Brightness Equatorial Spectrophotometric Standards
We have obtained spectral energy distributions for 41 7m 8m stars nearthe celestial equator (δ=±3°). The λλ31007600 Å spectral range is studied with a spectral resolution of 50Å. The relative rms error in the visible is 1 2%, increasing to 35% towards the edges of the wavelength interval studied. All stars arereferenced to a single standard, the circumpolar star HD 221525. Thesynthetic colors of common stars are compared with those observed infour photometric systems: U BV, W BV R, uvby, and that of the TYCHOcatalog. The program stars are recommended as secondaryspectrophotometric standards.
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Intermediate-Brightness Spectrophotometric Standards. Standards Near +40° Declination
The second stage in our program to compile a list of regionalintermediate-brightness spectrophotometric standards has been completed.We have obtained spectral energy distributions for 24 stars withmagnitudes near +40° declination. The range λλ31007600 Å was studied with a spectral resolution of 50 Å. Therelative rms error of our results in the visible is 1 2%, increasing to3 5% toward the edges of the studied wavelength interval. All the starsare referenced to a single standard, the circumpolar star HD 221525. Theenergy distributions were used to compute color indices in the UBV,WBVR, and UPXY ZV S systems, as well as in the system of the TYCHOcatalog. The computed and observed values for stars in common with theTYCHO catalog are compared.
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Catalogue of Apparent Diameters and Absolute Radii of Stars (CADARS) - Third edition - Comments and statistics
The Catalogue, available at the Centre de Données Stellaires deStrasbourg, consists of 13 573 records concerning the results obtainedfrom different methods for 7778 stars, reported in the literature. Thefollowing data are listed for each star: identifications, apparentmagnitude, spectral type, apparent diameter in arcsec, absolute radiusin solar units, method of determination, reference, remarks. Commentsand statistics obtained from CADARS are given. The Catalogue isavailable 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/qcar?J/A+A/367/521
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The Tokyo PMC catalog 90-93: Catalog of positions of 6649 stars observed in 1990 through 1993 with Tokyo photoelectric meridian circle
The sixth annual catalog of the Tokyo Photoelectric Meridian Circle(PMC) is presented for 6649 stars which were observed at least two timesin January 1990 through March 1993. The mean positions of the starsobserved are given in the catalog at the corresponding mean epochs ofobservations of individual stars. The coordinates of the catalog arebased on the FK5 system, and referred to the equinox and equator ofJ2000.0. The mean local deviations of the observed positions from theFK5 catalog positions are constructed for the basic FK5 stars to comparewith those of the Tokyo PMC Catalog 89 and preliminary Hipparcos resultsof H30.
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Fast digital spectrophometry of celestial bodies
An original digital slitless spectrophotometer with transparentdiffraction gratings has constructed, adjusted, and tested at theCrimean Astrophysical Observatory. It is mounted on the 0.5-m meniscustelescope, has high sensitivity, and enables spectrophotometricobservations of celestial bodies in the region 370-740 nm with exposureof several minutes and absolute photometric accuracy of several percent.The spectrophotometer is intended for studies of rapid variations in thespectra of stars, asteroids, comet nuclei, bright galactic nuclei, etc.
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Intrinsic Energy Distribution in Stellar Spectra in the Wavelength Interval 320--760 NM
The intrinsic energy distributions in the interval 320--760 nm ofspectral types B5--G8 of luminosity V, F0--F5 of luminosity IV andG8--M2 of luminosity III, determined by authors, are intercompared withthe catalogue of the mean energy distribution data published bySviderskiene (1988).
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The Stromvil System: an Effective Combination of Two Medium-Band Photometric Systems
It is shown that the addition to the Stromgren four-color photometricsystem of three passbands at 374, 516 and 656 nm from the Vilniusphotometric system makes the combined system more universal. This newsystem, called the Stromvil system, makes it possible to classify starsof all spectral types, even in the presence of interstellar reddening.This property of the system is especially important in CCD photometry,allowing the photometric classification of very faint stars. Apreliminary calibration of the system in terms of spectral andluminosity classes, temperatures and surface gravities is available. Alist of preliminary standards for the Stromvil system in the regions ofCygnus, Aquila and near the North Celestial Pole is given.
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UvbyHbeta_ photometry of main sequence A type stars.
We present Stroemgren uvby and Hbeta_ photometry for a set of575 northern main sequence A type stars, most of them belonging to theHipparcos Input Catalogue, with V from 5mag to 10mag and with knownradial velocities. These observations enlarge the catalogue we began tocompile some years ago to more than 1500 stars. Our catalogue includeskinematic and astrophysical data for each star. Our future goal is toperform an accurate analysis of the kinematical behaviour of these starsin the solar neighbourhood.
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Analysis of spectrophotometric and photometric data for primary spectrophotometric standards.
Not Available
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The Relation between Rotational Velocities and Spectral Peculiarities among A-Type Stars
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1995ApJS...99..135A&db_key=AST
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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.
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Regional Spectrophotometric Standards of Intermediate Brightness - Standards around the Northern Celestial Pole
Not Available
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HD 221525 as a primary spectrophotometric standard star in the visible
Not Available
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Fifth fundamental catalogue. Part 2: The FK5 extension - new fundamental stars
The mean positions and proper motions for 3117 new fundamental starsessentially in the magnitude range about 4.5 to 9.5 are given in thisFK5 extension. Mean apparent visual magnitude is 7.2 and is on average2.5 magnitudes fainter then the basic FK5 which has a mean magnitude of4.7. (The basic FK5 gives the mean positions and proper motions for theclassical 1535 fundamental stars). The following are discussed: theobservational material, reduction of observations, star selection, andthe system for the FK5 extension. An explanation and description of thecatalog are given. The catalog of 3117 fundamental stars for the equinoxand epoch J2000.0 and B1950.0 is presented. The parallaxes and radialvelocities for 22 extension stars with large forecasting effects aregiven. Catalogs used in the compilation of the FK5 fundamental catalogare listed.
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The study of the variability of primary standard group stars of the WBVR photometric system
Not Available
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Photoelectric photometry of bright stars in the vicinity of the North Celestial Pole
Not Available
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A. de Sitter's photographic polar photometry revisited; some remarks on photographic photometry with objective gratings
Not Available
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Search for Bright Star Variability in the North Pole Field
Not Available
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On the Reality of Some Peaks in Redshift Distribution of Seyfert Galaxies - Radio Galaxies and QSOS
Not Available
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On Possible Variability of Some Photometric Standards
Not Available
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Two catalogues of FK4 right-ascension corrections and their application
The results of observations conducted as part of the regular timeservice with transit instruments at the Borowiec and BratislavaObservatories were used to work out catalogs of right-ascensioncorrections of the FK4 stars, included in the observational programs.The characteristics of both catalogs are presented in the paper.Comparisons between the catalogs as well as their comparison with thecompilation catalog produced on the basis of observations performed withastrolabes are given. The results of applying these right-ascensioncorrections to the re-reduction of universal time are also presented.
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A new photometric WBVR system
A description of the new broad-band photometric system, WBVR, is given.It is shown that WBVR is close to the UBVR system but is defined bystrictly fixed response curves and the primary standard. Theconstruction of a network of secondary standards distributed uniformlyin the northern sky, as well as the coordination of the magnitudes ofthe standards to the self-consistent system are discussed. All standardsare examined for a possible brightness variability and it is found thatno light variability exceeding 0.015 mag in amplitude is present andthat their average magnitude shows stability on a scale of severalyears. The individual WBVR observations of the standards are presentedin tables.
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The System of Highly Accurate Photoelectric Standards in WBVR Bands
Not Available
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Vertical-circle observations of the aberration of stellar light of different spectral types
Measurements of 9 stars of high declination generally confirm Becker'srelation between the constant of aberration and the spectral type of thestars. The right ascensions and the declinations of the 9 stars are alsodetermined. The relation between aberration and spectral type cannot beexplained by atmospheric dispersion. The relation does not affectmeasurements of trigonometric parallaxes.
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Spectral classification of the bright F stars.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1976PASP...88...95C&db_key=AST
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MK Spectral Types for Some Bright F Stars
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1974PASP...86...70C&db_key=AST
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Rotation of evolving A and F stars.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1972A&A....18..428D&db_key=AST
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Six-color photometry of stars. VIII. The colors of 409 stars of different spectral types
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1956ApJ...123..440S&db_key=AST
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A photometric system
Not Available
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The Transfer of the North Polar Standards to the Southern Hemisphere.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1953ApJ...117...83C&db_key=AST
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NEWS@SKY (Science&Space News)
