|Spectra of binaries classified as lambda Bootis stars|
High angular resolution observations have shown that some starsclassified as lambda Boo are binaries with low values of angularseparation and magnitude difference of the components; therefore theobserved spectrum of these objects is a combination of those twocomponents. These composite spectra have been used to definespectroscopic criteria able to detect other binaries among starsclassified as lambda Boo. The application of this method to HD 111786 ispresented: the contribution of 5 components to the observed spectrum isdemonstrated by the shape of the O I 7774 Å feature. This resultmakes unreliable any attempt to perform an abundance analysis of thisobject which therefore must be definitely rejected from the class of thepeculiar lambda Boo stars. This approach allowed us also to recognizethat the SB2 star HD 153808 is in reality a triple system. Based on datafrom ESO, Observatoire du Pic du Midi, IUE Final Archive and onobservations obtained with the Hipparcos satellite.
|A Catalogue of Correlations Between Eclipsing Binaries and Other Categories of Double Stars|
Among the 9110 stars in The Bright Star Catalogue, there are 225eclipsing or ellipsoidal variables. A search has been made for these incatalogues of spectroscopic binaries, visual double or multiple stars,speckle interferometry, occulation binaries, and galatic clusters. Themajority of the photometric binaries are also members of groups ofhigher multiplicity. The variables are in systems ranging from one to 91stars, five on the average. 199 are either spectroscopic binaries (SB)or stars with variable radial velocity, with orbital periods known for160. Photometric periods are lacking for 48 while SB periods areavailable for 23 of these. Observers with photoelectric equipment areencouraged to plan observations to test if the SB periods are consistentwith photometric data. Observers are likewise encouraged to examinethose stars for which the photometric and SB periods appear to beinconsistent. Parallaxes are available for 86 of the stars, 41 of themindicating distances nearer than 50 parsecs.
|The Pulkovo Spectrophotometric Catalog of Bright Stars in the Range from 320 TO 1080 NM|
A spectrophotometric catalog is presented, combining results of numerousobservations made by Pulkovo astronomers at different observing sites.The catalog consists of three parts: the first contains the data for 602stars in the spectral range of 320--735 nm with a resolution of 5 nm,the second one contains 285 stars in the spectral range of 500--1080 nmwith a resolution of 10 nm and the third one contains 278 stars combinedfrom the preceding catalogs in the spectral range of 320--1080 nm with aresolution of 10 nm. The data are presented in absolute energy unitsW/m(2) m, with a step of 2.5 nm and with an accuracy not lower than1.5--2.0%.
|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
|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.
|The stellar temperature scale for stars of spectral types from O8 to F6 and the standard deviation of the MK spectral classification|
Empirical effective temperature of 211 early-type stars found in aprevious investigation (Kontizas and Theodossiou, 1980; Theodossiou,1985) are combined with the effective temperatures of 313 early-typestars from the literature. From these effective temperatures of a totalnumber of 524 early-type stars of spectral types from O8 to F6 a newstellar temperature scale is developed along with the standard deviationof the MK spectral classification.
|The early A type stars - Refined MK classification, confrontation with Stroemgren photometry, and the effects of rotation|
The MK classification system for the early A-type stars is refined, anda parallel system of standards for the broad-lined stars is introduced.With this improved system, stars may be classified with significantlygreater precision than before. It is shown that spectral types in thissystem are not systematically affected by rotational line broadening. Atotal of 372 early A-type stars are classified, and a confrontation ofthese spectral types with Stroemgren photometry reveals a number ofsystematic photometric effects of rotation. In particular, high v sin istars are systematically redder than low v sin i stars of the samespectral type, and the beta index is weakened by rotation. It isconcluded that precise spectral classification in conjunction withStroemgren and H-beta photometry can potentially provide a valuablecheck and input to the theory of the atmospheres of rotating stars.
|Catalogue of the energy distribution data in spectra of stars in the uniform spectrophotometric system.|
|Area Scanner Observations of Close Visual Double Stars - Part Two - Results for 153 Southern Stars|
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1983MNRAS.202..761H&db_key=AST
|Picture gallery - A structured presentation of OAO-2 photometric data supported by OAO-2 spectrophotometric data and UBV, ANS and TD1 observations|
Graphs are presented for the stellar fluxes of 531 stars in the5500-1330 A wavelength range, which have been divided into 52 categorieson the basis of spectral types. The merging of medium band interferencefilter photometry, UBV photometry, ANS photometry and TD1 fluxes, aswell as the ordering of the objects, should prove helpful in studies ofinterstellar reddening, luminosity effects, bandwidth effects, andcomparisons with model stellar atmospheres. The agreement between thevarious UV photometric systems for early-type stars is generally betterthan 0.10 mag. A list of stars whose photometric properties indicatestellar or interstellar anomalies is also provided.
|Standard Stars for Hα Photometry|
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1981A&AS...44..337S&db_key=AST
|Erratum - Discordances Between SAO and HD Numbers for Bright Stars|
|Ultraviolet photometry from the Orbiting Astronomical Observatory. XXXIV - Filter photometry of 531 stars of diverse types|
Ultraviolet magnitudes for 531 stars observed with the WisconsinExperiment Package on OAO 2 are tabulated. It is noted that these dataconstitute a subset of the OAO 2 data on file at the National SpaceScience Data Center. The tabulation contains previously published dataall reduced to a uniform magnitude system. It is pointed out that theobservations were obtained with the medium band interference filterphotometers. Eleven magnitudes are given designated by their centroidwavelengths.
|UVBY BET photometry of equatorial and southern bright stars.|
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1977A&AS...27...47H&db_key=AST
|A system of standard stars for rotational velocity determinations|
Profiles for the He I lambda 4471, Mg II lambda 4481, and Fe I lambda4476 lines were measured in the spectra of 217 bright northern andsouthern stars of types O9-F9, using photoelectric scans andphotographic coude spectrograms obtained at the Cerro TololoInter-American Observatory, Kitt Peak National Observatory, and LowellObservatory. Half-intensity widths of the observed line profiles werecompared with the corresponding quantities in a set of theoreticalrotationally-broadened line profiles computed using the model-atmosphereapproach. The resulting v sin i's are used to establish a system ofstandard rotational velocity stars, for use in estimating v sin idirectly from visual inspection of spectrograms. An atlas ofrotationally broadened spectra is presented, showing the effects ofrotation on spectra of representative B-, A-, and F-type stars.
|Four-colour and H-beta photometry for bright stars in the southern hemisphere.|
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1970AJ.....75..624C&db_key=AST
|The galactic force law K(z|
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1969AJ.....74..139P&db_key=AST
|Résultats des observations faites à Tananarive avec l'Astrolabe A. Danjon|
|BVRI Photoelectric Photometry for 275 Stars located between -25° y -50° Fotometría Fotoeléctrica en BVRI para 275 estrellas comprendidas en su mayoría entre -25° y -50°|
BYRI photometry in Johnson's system was done for 275 stars the mayority ofwhich are comprised between -25° and -50°. Due to systematicvariations in V magnitude in R. A. of the order of 0.2 magnitude it wasdecided to use in the present work V magnitudes of the Catalogue of theRoyal Observatory, Cape of Good Hope, South Africa. The colours presentedhere, should permit to have an homogeneous R and I Systems of photometryfor both the Northern and Southern sky, complete to the fifth magnitude, anup to -50° in declination
|Recherches sur les Proprietes des Etoiles Doubles ou Multiples Largement Separees EN Relation avec les Problemes d'Evolution. Tabl. IX|
|Research work at the Washburn Observatory. Stellar parallax, the lunar atmosphere, the ocular heliometer.|