The Naini Tal - Cape survey for pulsations in chemically peculiar A-type stars. I. Methods and preliminary results
A new survey for pulsating, chemically peculiar A- and F-type stars inthe northern hemisphere has been initiated using the 1-m telescope atUttar Pradesh State Observatory in Naini Tal. The survey is primarilystructured to reveal high-overtone pulsations in chemically peculiar A-Fstars, but it is also revealing low-overtone delta Scuti-type pulsationsin stars with peculiar colours. This paper describes the scope andmethods of the survey. Preliminary observations of 28 candidate starsare presented and the discovery of three new pulsators, HD 12098, HD13038 and HD 13079, is announced. Null results for the remaining 25stars are also discussed.
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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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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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Photometric and spectroscopic analysis of high galactic latitude molecular clouds. II - High-resolution spectroscopic observations of NA I, CA II, CA I, CH, and CH(+1)
High-resolution spectroscopic observations in the wavelengths of thespecies Na I, Ca II, and Ca I and the molecular species CH and CH(+)have been performed toward stars behind a variety of high galacticlatitude molecular clouds (HLCs). Seventeen new detections of molecularabsorption are reported. The sizes, densities, and molecular contentfound for the HLCs are consistent with an interpretation of HLCmolecular cores as extremely compact structures of enhanced molecularcontent which may have evolved from larger H I shells.
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Maximum separations among cataloged binaries
The paper classifies many of the widest common-motion binaries listed inthe Aitken catalog and list 72 physical pairs with known photoelectricphotometry, 31 physical pairs without good photometry, and 27 opticalpairs. As a function of primary types, the physical systems have upperlimits to their separations that are exceeded by some of the opticalpairs. The fact that optical pairs occur with larger separations impliesthat the limits are real ones and not just catalog limitations. Thoselimits (in AU) are expressed by 2500 M1 exp 1.54 for B5-KO main-sequenceprimaries. The same limits hold for the Trapezium and hierarchicalsystems studied previously.
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Photoelectric UBV-photometry of triple-star components
Photoelectric UBV photometry was performed on components of 30 brightand nearby triple stars to identify physically linked triple systems andto determine their distances and dynamic evolution. An analysis of 60catalogs showed only 10 triple systems. For every component, E(B-V) andE(U-B) color excesses are determined and photometric parallaxes arecalculated using available spectral types.
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Common proper motion stars in the AGK 3
A search was made of common-proper-motion (CPM) systems among AGK 3stars. The selection of physical systems was based upon the ratiobetween the angular separation (rho) and the proper motion (mu); the CPMstars found are presented in two tables. Table I lists systems withrho/mu less than 1000 years. It contains 326 entries, and the proportionof optical pairs is estimated to be 1 percent. Table II lists systemswith rho/mu in the range 1000 to 3500 years; it contains 113 systems,but only 60 percent of them are physical. Nevertheless, these systemsoften have separations larger than 10,000 AU and are the mostinteresting for the study of the tail of the distribution function ofthe semimajor axes.
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The nature of the visual companions of AP and AM stars
The stars in 43 visual multiples with Ap or Am primaries have beenclassified, and the fraction of systems that have Ap or Am secondariesis counted. The numbers of Ap secondaries are too few to be informative,but an apparent excess of Am secondaries is found. That result isunderstandable in terms of the (published) moderate correlation inrotational velocities between components in visual multiples. But invarious open clusters, the variations in frequencies of Ap and Am starscan be explained probably as statistical fluctuations in small numbersof stars, indicating no tendency for abnormal stars to group togetherfor dimensions larger than those of visual multiples.
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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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Supplement to the Second Catalogue of Am Stars with Known Spectral Types (end 1981)
Not Available
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UVBY beta study of A-and F-type visual binaries. I.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1976AJ.....81..107M&db_key=AST
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Rotational velocities and spectral types for a sample of binary systems.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1975A&AS...19...91L&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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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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UVBY photometry of AM and AP stars.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1973AJ.....78..192W&db_key=AST
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Catalog of Indidual Radial Velocities, 0h-12h, Measured by Astronomers of the Mount Wilson Observatory
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1970ApJS...19..387A&db_key=AST
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Observations spectrographiques d'etoiles A a spectre particulier et a raies metalliques.
Not Available
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Catalogue des étoiles mesurées dans le système photométrique de l'Observatoire de Genève
Not Available
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Catalogue et bibliographie des étoiles A à spectre particulier - Deuxième supplément
Not Available
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Three-color photometry of the components in 228 wide double and multiple systems.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1963AJ.....68..483E&db_key=AST
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Some Remarks on Metallic-Line Stars. With 3 figures in the text.
Not Available
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Classification d'étoiles doubles dans le système à 3 paramètres λ,D, Φb
Not Available
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Mesures photométriques d'étoiles doubles écartées au moyen d'un apparell nouveau
Not Available
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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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A survey of stars with composite spectra.
Not Available
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INHABITED SKY
