Optical and Radio Monitoring of S5 1803+784
The optical (BVRI) and radio (8.4 GHz) light curves of S5 1803+784 on atime span of nearly 6 yr are presented and discussed. The optical lightcurve showed an overall variation greater than 3 mag, and the largestchanges occurred in three strong flares. No periodicity was found in thelight curve on timescales up to a year. The variability in the radioband is very different and shows moderate oscillations around an averageconstant flux density rather than relevant flares, with a maximumamplitude of ~30%, without a simultaneous correspondence between opticaland radio luminosity. The optical spectral energy distribution wasalways well fitted by a power law. The spectral index shows smallvariations, and there is indication of a positive correlation with thesource luminosity. Possible explanations of the source behavior arediscussed in the framework of current models.
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A Period Study of the Eclipsing Binary System W Ursae Minoris
The variation of the period of W UMi is investigated. It is shown thata sudden period decrease occurred in this system.
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On the HIPPARCOS photometry of chemically peculiar B, A, and F stars
The Hipparcos photometry of the Chemically Peculiar main sequence B, A,and F stars is examined for variability. Some non-magnetic CP stars,Mercury-Manganese and metallic-line stars, which according to canonicalwisdom should not be variable, may be variable and are identified forfurther study. Some potentially important magnetic CP stars are noted.Tables 1, 2, and 3 are available only in electronic form at the CDS viaanonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or viahttp://cdsweb.u-strasbg.fr/Abstract.html
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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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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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Lists of photometric AM candidates
The Geneva photometric m parameter (Nicolet and Cramer, 1982) is used inorder to select Am photometric candidates from the Rufener (1981)catalogue. Two lists are given, the first containing field stars and thesecond cluster stars. According to the photometric criteria thediffusion process probably responsible for the Am phenomenon takes placerather quickly as Am candidates are present in young clusters. It isconfirmed that the phenomenon is enhanced by low rotational velocity andhigh metallicity. The age seems to slightly affect the Am phenomenon.
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Erratum - Discordances Between SAO and HD Numbers for Bright Stars
Not Available
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Properties of AM stars in the Geneva photometric system
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1980A&A....92..289H&db_key=AST
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Metallicism and pulsation - The marginal metallic line stars
Evidence is presented that HR 4594 and HR 8210 are pulsating marginal Amstars. It is suggested that (1) classical Am stars do not pulsate, (2)evolved Am stars may pulsate, and (3) marginal Am stars may pulsate. Itis further suggested that, within the Am domain, temperature, age,rotation, and pulsation are sufficient to determine whether a star willbe Am, marginal Am, or spectrally normal.
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Bright metallic-line and pulsating A stars.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1976PASP...88..402E&db_key=AST
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Multicolor photometry of metallic-line stars. III. A photometric catalogue
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1974RMxAA...1..175M&db_key=AST
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Rotation and shell spectra among A-type dwarfs.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1973ApJ...182..809A&db_key=AST
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Catalogue of AM stars with known spectral types
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1973A&AS...10..385H&db_key=AST
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Two Independent Photoelectric Light Curves and Solutions of W Ursae Minoris
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1970PASP...82...10D&db_key=AST
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Catalogue et bibliographie des étoiles A à spectre particulier - Deuxième supplément
Not Available
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Six-Color Photometry of Stars. XI. Black-Body Color Temperatures of 25 Stars.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1964ApJ...139..424S&db_key=AST
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Variazioni delle latitudini E constante DI aberrazione annua 1951-52 nel sistema FK3.
Not Available
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Catalogue et bibliographie des étoiles A à spectre particulier Premier supplément
Not Available
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Catalogue et bibliographie des étoiles A à spectre particulier
Not Available
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Six-Color Photometry of Stars. X. The Stellar Magnitude and Color Index of the Sun.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1957ApJ...126..266S&db_key=AST
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Absolute magnitudes, colors, masses and duplicity of the metallic-line stars.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1957AJ.....62..343J&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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Sur la détermination de la grandeur de la discontinuité de Balmer par les méthodes de la photométrie à travers des filtres
Not Available
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Photoelectric Studies. VII. Color and Magnitude Systems for Brighter Stars and the Color-Spectral Relation.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1951ApJ...113..663E&db_key=AST
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Red and Infrared Magnitudes for 125 Stars in Ten Areas
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1951ApJ...113..324K&db_key=AST
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Electrical photometry of stars and nebulae (George Darwin Lecture)
Not Available
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INHABITED SKY
