Evolution of interacting binaries with a B type primary at birth
We revisited the analytical expression for the mass ratio distributionfor non-evolved binaries with a B type primary. Selection effectsgoverning the observations were taken into account in order to comparetheory with observations. Theory was optimized so as to fit best withthe observed q-distribution of SB1s and SB2s. The accuracy of thistheoretical mass ratio distribution function is severely hindered by theuncertainties on the observations. We present a library of evolutionarycomputations for binaries with a B type primary at birth. Some liberalcomputations including loss of mass and angular momentum during binaryevolution are added to an extensive grid of conservative calculations.Our computations are compared statistically to the observeddistributions of orbital periods and mass ratios of Algols. ConservativeRoche Lobe Over Flow (RLOF) reproduces the observed distribution oforbital periods but fails to explain the observed mass ratios in therange q in [0.4-1]. In order to obtain a better fit the binaries have tolose a significant amount of matter, without losing much angularmomentum.
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Circular Polarization of Starlight
Of the 7500 stars cited in the Catalog of starlight polarization, thosewhich satisfy the condition P obs % and A V 0m.5 are selected. It ispresumed that the selected stars (n=216) have circularly polarizedlight.
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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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CCD Stromgren Photometry of Young Reddened Clusters
The capabilities of CCD uvby photometry for the study of reddened youngclusters are investigated. Observations of four fields in the directionof the clusters Basel 1, Berkeley 86, NGC 6704, and NGC 6756, with atotal of 1665 stars measured in at least the y and b bands, produce newestimates for the clusters parameters. The results are compared to thosefrom previously published studies in different photometric systemsshowing good agreement in the values of color excess and distancemodulus, with the exception of NGC 6756, for which an essentially largerdistance is found. Furthermore, the ages estimated for this cluster,Basel 1, and NGC 6704 are found to be higher than previously assumed, inparticular for the last one. The presence of red giants as clustermembers is suggested in Basel 1, NGC 6704, and NGC 6756.
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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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Photometry of Stars in the Field of V345 and V553 Aquilae
Not Available
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Photometry of Stars in the Field of the Mira EL Lyrae
Not Available
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Teff and log g determinations for 25 CP stars from Hβ profiles.
Not Available
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Uvby-beta observations of 528 type B stars with V between the 8th and 9th magnitude
The paper presents uvby-beta measurements of 528 type B stars selectedfrom the SAO Catalog on the basis of two criteria: the spectral types inthe range B3-B5 and mV between the 8th and the 9th magnitude. Reddeningindependent (c1) values are estimated from the spectral classificationand compared to the observed values. No systematic trend with observed(b-y), H-beta, or spectral type appears to be present, but the range of(c1) residuals is surprisingly large. A rather large part of the starshas small beta values, smaller than for the BIa supergiants. Only twoare classified as O stars and most of them have the suffix e, ne, ornne. Most beta values for the O type stars are slightly above the upperlimit of 2.585 m.
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UBV(RI)c photometry of equatorial standard stars - A direct comparison between the northern and southern systems
UBV(RI)c photometry of 212 stars from Landolt's list of equatorialstandards is presented. The observations are tied to the system definedby Cousin's E-region standards. A comparison of the present results withLandolt's reveals reasonably good agreement for (V-R)c and (V-I)c, butmarked systematic differences for (B-V) and (U-B). The UBV systems ofCousins and Landolt are evidently not the same and both probably differfrom Johnson's original system.
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Photometric Variations of AS296
Photometric observations of the symbiotic star AS296 in U, B, V duringthe past three years are described and the need for more observations isstressed.
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Close binaries observed polarimetrically
Not Available
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Empirical temperature calibrations for early-type stars
Three temperature calibrations of suitable photometric quantities havebeen derived for O and B stars. A sample of 120 stars with reliableT(eff.) determinations has been used for establishing each calibration.The different calibrations have been critically discussed and compared.Temperature determinations for 1009 program stars have been obtainedwith an accuracy of the order of 10 percent.
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Catalog of O-B stars observed with Tokyo Meridian Circle
A catalog of the O-B stars, selected from 'Blaauw-Parenago' list andRubin's catalog, has been compiled on the FK4 system by the observationsmade with Gautier 8-inch Meridian Circle at the Tokyo AstronomicalObservatory during the period, 1971 to 1979. It contains 1059 stars andwas compiled for the future establishment of high precision propermotions of O-B stars.
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Observations of the polarization of the radiation of R-association stars
A Ritchey-Chretien 1-m telescope was used to perform observations of thepolarization parameters of the radiation of stars in the reflectionnebulae in the regions of Cas, Per R1, Ser, and CMa R1. The connectionbetween the polarization vector and the structure of the nebulae isconsidered, and it is shown that the occurrence of polarization is dueboth to the absorption of the light of the stars and to scattering byelongated dust grains. The orientation of the grains is due to themagnetic field.
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The period distribution of unevolved close binary systems
Period distributions have been examined for various spectral types ofabout 600 (eclipsing and spectroscopic) close binaries, which are likelyto be substantially unevolved. The comparison with the previouscorresponding analyses of extensive (but heterogeneous) binary samplesallows a clarification of the extent of the evolutionary andobservational selection effects. Remarkably, this analysis reveals agreat deficiency of short period binaries (with periods corresponding tocase A mass transfer) in the whole spectral range. For the late spectraltypes, this result may be connected with postformation angular momentumloss caused by stellar wind magnetic braking; at least for the late Band A spectral range, a ready interpretation of this finding is thatclose binaries of corresponding periods and spectral types are rarelyformed.
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Synchronization in early-type spectroscopic binary stars
The rotational properties of a large sample of noneclipsing double-linedspectroscopic binaries are discussed in terms of synchronization ofaxial and orbital rotation. The data covered the spectral types OB andA04, i.e., those with full radiative envelopes. Nearly 80 systems wereinvestigated, and the periods and orbital velocities are provided. Ahigh correlation was found between the fractional radius and theoccurrence of synchronicity and pseudosynchronicity. Deviations fromsynchronous rotation were most apparent at fractional radii of 0.05 andbelow. Current theories of the synchronization time scales are noted tobe inadequate for describing the small fractional radii-lack ofsynchronism observed.
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UBVRI photometric standard stars around the celestial equator
It is pointed out that accurate, internally consistent, and readilyaccessible standard star photometric sequences are necessary for thecalibration of the intensity and color data which astronomers obtain atthe telescope. The photometric results provided in connection with thepresent study represent the first part of an effort which is concernedwith the presentation of UBVRI photoelectric photometric standard starsin the magnitude range from 7 to 17 over as broad a range in color aspossible. All of the photometric observations were made with a 31034type photomultiplier used in a pulse counting mode. Some 15 to 25standard stars chosen from Cousins' lists (1973, 1976) in the E-regionswere observed with an 0.4-m telescope each night along with the programstars. UBVRI standard stars were observed periodically throughout thenight. Observations with a 0.9-m telescope were also conducted. TheUBVRI photoelectric observations take into account 223 stars.
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The interstellar extinction law in some dusty HII regions
UBVRI data for 62 O and B stars in dusty H II regions and for nine fieldstars are presented. The data are used to investigate the reddening lawin the range BVRI. For the field stars and the H II regions M8, M20, S5,S66, S67, the normal interstellar extinction law has been confirmed.However, in NGC 6334, NGC 6357 and M16 unusually high color excessratios have been found: E(V-R)/E(B-V) and E(V-I)/E(B-V), indicatingabnormal values of the ratio of total to selective extinction, R equals3.8 for NGC 6334/6357 and R equals 4.0 for M16.
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Seventh catalogue of the orbital elements of spectroscopic binary systems.
Not Available
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Correlations of the band at 2175 A with other interstellar features
Using published spectrophotometric and filter-photometric data from theOAO-2 and TD-1A satellites, equivalent widths of the ultraviolet 2175-Aband are determined for 194 stars. This list of data is used to studycorrelations between the 2175-A band and the diffuse 4430-A, 5780-A, and5797-A bands as well as the hydrogen column density and the equivalentwidth of the sodium D2 line.
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Photoelectric measures of variable stars observed at MT. Kobau (1970-73).
Not Available
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The correlation between the ultraviolet lambda 2200 feature and the diffuse lambda 4430 band.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1975MNRAS.173..237N&db_key=AST
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Equivalent widths and rotational velocities of southern early-type stars
Not Available
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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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Photoelectric 4430 A observations of 506 O, B and A stars.
Not Available
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Troisième catalogue de l'Observatoire de Besançon comprenant 764 étoiles réduites à 1950, 0 sans mouvement propre et 326 étoiles FK3 pour l'époque moyenne d'observation
Not Available
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Report of proceedings of Victoria, Dominion Astrophysical Observatory
Not Available
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Polarization of Stellar Radiation. III. The Polarization of 841 Stars.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1951ApJ...114..241H&db_key=AST
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