uvby FCAPT Photometry of the Magnetic Chemically Peculiar Stars 36 Aurigae, HR 2722, 13 Andromedae, and HD 220147
Differential Strömgren uvby observations obtained with the FourCollege Automated Photoelectric Telescope (FCAPT) are presented for themagnetic chemically peculiar (mCP) stars 36 Aur, HR 2722, 13 And, and HD220147. The new data help to better define the light curves. The periodfor 36 Aur was found to be 14.368 days, close to that for the previousstudy with FCAPT data. The period for HR 2722 is unchanged, at 2.31523days. Comparisons between Hipparcos and FCAPT photometry were used torefine the periods individually derived by each source to 1.47931 daysfor 13 And and to 10.983 days for HD 220147.
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Rotational Velocities of B, A, and Early-F Narrow-lined Stars
Projected rotational velocities for 58 B, A, and early-F stars have beendetermined from high-resolution spectroscopic observations made at KittPeak National Observatory with the coudé feed telescope. All thestars are slowly rotating with vsini<60 km s-1. Because oftheir low rotational velocities, 15 of the stars have been observed asprospective, early-type, radial velocity standards.
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uvby FCAPT photometry of the metallic-lined stars 60 Tau and HR 1528 and the magnetic CP stars HR 8216 and HR 8770
Differential Strömgren uvby observations from the Four CollegeAutomated Photoelectric Telescope (FCAPT) are presented for themetallic-lined stars 60 Tau and HR 1528 and the magnetic ChemicallyPeculiar stars HR 8216 and HR 8770. The first star, which is a deltaScuti variable, was found not to change its mean magnitudes. HR 1528 isbest described as constant. A decade of photometry of HR 8216 shows thatits b and y values have changed by -0.016 and -0.010 mag, respectively,over this time and now can be considered a photometric variable. For HR8770 a period of 5.3923 days is derived with the photometric variabilitybeing generally in phase. The light curves also suggest possible surfaceabundance inhomogeneities.Tables 2, 3, 4 and 6 are only available in electronic form at the CDSvia anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or viahttp://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/401/357
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Rotational velocities of A-type stars in the northern hemisphere. II. Measurement of v sin i
This work is the second part of the set of measurements of v sin i forA-type stars, begun by Royer et al. (\cite{Ror_02a}). Spectra of 249 B8to F2-type stars brighter than V=7 have been collected at Observatoirede Haute-Provence (OHP). Fourier transforms of several line profiles inthe range 4200-4600 Å are used to derive v sin i from thefrequency of the first zero. Statistical analysis of the sampleindicates that measurement error mainly depends on v sin i and thisrelative error of the rotational velocity is found to be about 5% onaverage. The systematic shift with respect to standard values fromSlettebak et al. (\cite{Slk_75}), previously found in the first paper,is here confirmed. Comparisons with data from the literature agree withour findings: v sin i values from Slettebak et al. are underestimatedand the relation between both scales follows a linear law ensuremath vsin inew = 1.03 v sin iold+7.7. Finally, thesedata are combined with those from the previous paper (Royer et al.\cite{Ror_02a}), together with the catalogue of Abt & Morrell(\cite{AbtMol95}). The resulting sample includes some 2150 stars withhomogenized rotational velocities. Based on observations made atObservatoire de Haute Provence (CNRS), France. Tables \ref{results} and\ref{merging} are only available in electronic form at the CDS viaanonymous ftp to cdsarc.u-strasbg.fr (130.79.125.5) or viahttp://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/393/897
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The Physical Basis of Luminosity Classification in the Late A-, F-, and Early G-Type Stars. I. Precise Spectral Types for 372 Stars
This is the first in a series of two papers that address the problem ofthe physical nature of luminosity classification in the late A-, F-, andearly G-type stars. In this paper, we present precise spectralclassifications of 372 stars on the MK system. For those stars in theset with Strömgren uvbyβ photometry, we derive reddenings andpresent a calibration of MK temperature types in terms of the intrinsicStrömgren (b-y)0 index. We also examine the relationshipbetween the luminosity class and the Strömgren c1 index,which measures the Balmer jump. The second paper will address thederivation of the physical parameters of these stars, and therelationships between these physical parameters and the luminosityclass. Stars classified in this paper include one new λ Bootisstar and 10 of the F- and G-type dwarfs with recently discoveredplanets.
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Atmospheric abundances in post-AGB candidates of intermediate temperature
Detailed atmospheric abundances have been calculated for a sample of -Gsupergiant stars with IR fluxes and/or high galactic latitudes. HD172481 and HD 158616 show clear indications of being post-AGB stars thathave experienced third dredge-up. HD 158616 is carbon-rich while theabundance pattern of HD 172481 and its large Li enhancement givessupport to the hot bottom burning scenario that explains paucity ofcarbon-rich stars among AGB stars. HD 172324 is very likely a hotpost-AGB star that shows a strong carbon deficiency. HD 725, HD 218753and HD 331319 also appear to be evolved objects between the red giantand the AGB. HD 9167, HD 173638 with a few exceptions, reflect solarabundances and no signs of post red giant evolution. They are mostlikely young massive disk supergiants. Further analysis ofproto-Planetary Nebula HDE 341617 reveals that He lines show signs ofvelocity stratification. The emission lines have weakened considerablysince 1993. The envelope expands at 19 km s-1 relative to thestar. Atmospheric abundances, evolutionary tracks and isochrones areused to estimate masses and ages of all stars in the sample. Based onobservations obtained at the Haute-Provence Observatory, France. Tables11 and 12 are only available in electronic form athttp://www.edpsciences.org
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UBV beta Database for Case-Hamburg Northern and Southern Luminous Stars
A database of photoelectric UBV beta photometry for stars listed in theCase-Hamburg northern and southern Milky Way luminous stars surveys hasbeen compiled from the original research literature. Consisting of over16,000 observations of some 7300 stars from over 500 sources, thisdatabase constitutes the most complete compilation of such photometryavailable for intrinsically luminous stars around the Galactic plane.Over 5000 stars listed in the Case-Hamburg surveys still lackfundamental photometric data.
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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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An O-C diagram analysis of PV Cassiopeiae
Basing on recent and old photoelectric times of minimum, a new slightlylonger period of the apsidal motion for an eclipsing binary PV Cas hasbeen obtained. A difference between observed and theoretical periods ofthe apsidal motion estimated on the base of Claret and Gimenez modelsgrowed up to 30 years is found.
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Third preliminary catalogue of stars observed with the photoelectric astrolabe of the Beijing Astronomical Observatory.
Not Available
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Miscellaneous spectroscopic notes
Results of slit-spectrograph observations are reported for approximately260 stars. The data presented range from recognition of many new Ap, Am,and other unusual stars to H-alpha observations of early-typesupergiants and Be stars. The material discussed was obtained over thepast 40 years at a number of U.S. observatories and at the DominionAstrophysical Observatory in Victoria, B.C.
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Spectral classification of middle-type supergiants in the photographic infrared
A semiquantitative spectral classification scheme for middle-typesupergiant stars is presented which is wholly dependent on data in thenear infrared. The method involves the measurement of central depths asindicators of the strengths of the Paschen hydrogen lines 12 through 16,the Ca II infrared triplet and the 7774-A blend of O I, and was testedon slit spectrograms of previously classified stars of spectral types B8through G2. Results for the 142 stars considered are found to agree wellwith the MK spectral types determined previously, particularly inspectral types A5 through G0 and luminosity classes Ia through II.
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Prediction of spectral classification from photometric observations - Application of the UVBY beta photometry and the MK spectra classification. II - General case
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1980A&A....85...93M&db_key=AST
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Prediction of spectral classification from photometric observations-application to the UVBY beta photometry and the MK spectral classification. I - Prediction assuming a luminosity class
An algorithm based on multiple stepwise and isotonic regressions isdeveloped for the prediction of spectral classification from photometricdata. The prediction assumes a luminosity class with reference touvbybeta photometry and the MK spectral classification. The precisionattained is about 90 percent and 80 percent probability of being withinone spectral subtype respectively for luminosity groups I and V and forluminosity groups III and IV. A list of stars for which discrepanciesappear between photometry and spectral classification is given.
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Detection of errors in spectral classification by cluster analysis
Cluster analysis methods are applied to the photometric catalogue ofuvby-beta measurements by Hauck and Lindemann (1973) and point out 249stars the spectral type of which should be reconsidered or thephotometric indices of which should be redetermined.
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UBV photoelectric photometry of the components of 20 young stellar multiple systems
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1976A&AS...24...89B&db_key=AST
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Investigations on the intrinsic properties of high-luminosity blue stars inferred from observations of multiple systems
Spectrophotometric BCD and photometric UBV data are reported andanalyzed for O stars and blue giants that are the brightest members ofsome multiple system. Spectrophotometric parameters obtained were: thevisible gradient phi-rb, the blue gradient phi-b, the ultravioletgradient phi-uv, the Balmer discontinuity D, and the position of theBalmer discontinuity. Intrinsic colors obtained are bluer than Johnson'sscale, but redder than those of corresponding main sequence stars. Thespectrophotometric colors of the O stars were fairly dispersed, which isnot wholly attributed to the small number of measurements. Significantdisagreement was obtained between the colors obtained for the O starsand the generally accepted ones or those given theoretically by theclassical ETL or NETL models.
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Micrometer Measures of Double Stars.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1961ApJS....6....1K&db_key=AST
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The Light-Variability of Early B Giants.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1959ApJ...130..577L&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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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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Untersuchungen an Farbenindizes II. Mit 1 Textabbildung
Not Available
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Untersuchungen an Farbenindizes I. Mit 3 Textabbildungen
Not Available
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