New periodic variables from the Hipparcos epoch photometry
Two selection statistics are used to extract new candidate periodicvariables from the epoch photometry of the Hipparcos catalogue. Theprimary selection criterion is a signal-to-noise ratio. The dependenceof this statistic on the number of observations is calibrated usingabout 30000 randomly permuted Hipparcos data sets. A significance levelof 0.1 per cent is used to extract a first batch of candidate variables.The second criterion requires that the optimal frequency be unaffectedif the data are de-trended by low-order polynomials. We find 2675 newcandidate periodic variables, of which the majority (2082) are from theHipparcos`unsolved' variables. Potential problems with theinterpretation of the data (e.g. aliasing) are discussed.
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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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Red and infrared colours of B stars and the reddening law in the Galaxy
The red and infrared intrinsic colours of B stars are derived fromphotometric observations through the UBV(RI)_CJHK and Hβ filters of257 early-type stars. Those stars for which the UBV and Hβmeasurements match the published spectral class, and which show no othersigns of peculiarity, are used to determine the intrinsic photometriccolours of B stars in the red and infrared. From these intrinsic coloursthe interstellar reddening relationships for the red and infraredcolours are evaluated, and the results are compared with previousestimates of these quantities. The values of R, E(B-V) and the distanceare then determined for the individual stars. R is confirmed to be closeto 3.1 in most cases, but was found to be much larger in somedirections. The relationship between R and the location of a star in theGalaxy is investigated. Usually the abnormally reddened stars seemed tobe associated with known regions of star formation. The paper alsoidentifies seven likely variable stars and a number of stars withpossible dust shells.
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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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Extinction law survey based on UV ANS photometry
The paper presents an extensive survey of interstellar extinction curvesderived from the ANS photometric measurements of early type starsbelonging to our Galaxy. This survey is more extensive and deeper thanany other one, based on spectral data. The UV color excesses aredetermined with the aid of 'artificial standards', a new techniqueproposed by the authors which allows the special check of Sp/L match ofa target and the selected standard. The results indicate that extinctionlaw changes from place to place.
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Mass loss from stars : the universal formula for mass loss rate
Not Available
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The 69th Name-List of Variable Stars
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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Mass loss rates in the Hertzsprung-Russell diagram
Mass loss rates have been collected for 271 stars of spectral type Othrough M, primarily of population I. Good agreement is found forresults obtained according to six different methods, and it is shownthat the mass loss rate data can be well represented by one empiricalinterpolation formula as a function of the effective temperature andluminosity. The chemically evolved stars are shown to have mass lossrates which are larger than those of normal stars occupying the samepositions in the Hertzprung-Russell diagram by factors of 160 forWolf-Rayet stars and 11 for C-type stars.
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The interstellar 217 NM band - A third catalogue of equivalent widths
A catalog of equivalent widths of the 217 nm interstellar absorptionband as well as other parameters characterizing the extinction curve inthe ultraviolet has been compiled for 790 O and B stars. A relativelytight correlation between the equivalent width of the 217 nm band andE(B-V) indicates that the absorber of this band is connected with thepopulation of larger interstellar grains responsible for the visualextinction. The parameter characterizing the amount of extinction in thefar UV is only weakly correlated with E(B-V), a result in accord withthe assumption that a second population of very small grains causes therapid increase of the far-UV extinction.
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Observations of interstellar diffuse absorption band at 4430 A
Observations of the interstellar diffuse absorption band at 4430 A for800 O and B stars in Neckel's (1967) catalog are being carried out, and482 spectra obtained up to September 1983 have been reduced. It isconfirmed that the strength of the interstellar diffuse absorption bandat 4430 A does not simply relate to the abundance of interstellar grainson the line of sight. The relation between the color excess E(B-V) andthe equivalent width of the band to the direction of l = 130-140 deg andb = -5 to +5 deg shows that some parameter(s) other than E(B-V) is (are)needed to understand the cause of this band.
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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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Photometric Variations of the Supergiant B3 Ia: HD 178129
Not Available
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On absorption by hot interstellar gas. II - The 5303-A forbidden line of Fe XIV
Spectroscopic observations of 29 stars at 5303 A obtained with the coudespectrograph on the 2.7-m reflector at McDonald Observatory during1979-1983 are reported. Instrumental FWHM resolution is 27, 54, or 10pm, and detection limits near 100 fm equivalent width are obtained inoptimal cases. The results are presented in tables and a diagram. Noabsorption attributable to Fe XIV in hot interstellar gas is detectedexcept for HD 93521, on Apr. 10, 1981, only. This absorption can belocated either in interstellar gas at 1.2 million K or less with an FeXIV/Fe X ratio greater than 3 or in hot gas confined in an inhomogeneousstellar corona.
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On absorption by hot interstellar gas. I - Forbidden Fe X 6375
The spectra of 32 stars have been observed in the region of the coronalforbidden Fe X 6375 line at detection limits near an equivalent width of1 mA in the best cases. No absorption which can be attributed to Fe Xions in hot interstellar gas is seen in any of these spectra except one,in general agreement with predictions based on a three-phase model ofthe interstellar medium. Toward Cephei an absorption line is measuredwith an equivalent width of 8.1 + or - 2 mA, a width corresponding to 20+ or - 5 km/s or a temperature not greater than about (0.5 + or - 0.25)x 10 to the 6th K, and, if it is caused by Fe X ions, a radial velocityof -355 km/s. On that hypothesis, the hot interstellar gas constitutesat least 30 percent of the column density of gas along this light path.Six new telluric lines also are detected, and the 6376, 6379 A diffuseinterstellar bands are observed toward all six appreciably reddenedstars and one high-latitude star.
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New UBVRI photometry for 900 supergiants
A description is presented of the results obtained in connection with asystematic program of supergiant photometry on the Johnson UBVRI system.During the eight years after the start of the program, almost 1000 starshave been observed, about 400 three or more times each. The originalselection of stars used the spectral type catalog of Jaschek et al.(1964) to choose supergiants. Since observations were possible from bothChile and Canada, no declination limits were imposed, and no particularselection criteria were imposed other than to eliminate carbon stars.These are so red as to require enormous extrapolations of thetransformation equations.
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Observations in linearly polarized light of the intensity of the diffuse lam 6180 absorption band in 56 southern O, B and A stars.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1978A&A....70..195G&db_key=AST
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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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Spectroscopic measurements of OB Supergiants.
Not Available
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Stellar winds from hot supergiants
High-dispersion spectrographic data are described for 65 very luminousgalactic OB stars. Their absolute magnitudes and masses are estimated.Almost all the stars show evidence for mass outflow, and the flow rateis empirically calibrated from mass-loss models for a few of them.Approximate contours of mass-loss on the H-R diagram are suggested whichsupport the zero point of the individual rates. These are as high as onehundred-thousandth of a solar mass per year from a supergiant of 60solar masses. Anomalously high mass-loss rates found in a few stars maybe connected with duplicity of the objects.
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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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Observations of the diffuse 4430 A absorption band in southern O, B, and A stars
Photoelectric narrow-band observations of the intensity of the diffuseinterstellar 4430 A absorption band have been carried out for 65southern O, B and A stars of luminosity classes I and II. The dependenceof the 4430 A index on stellar spectral lines is eliminated and thevariation of the ratio Jc/E(B-V) of 4430-A wavelength to selectiveabsorption from place to place in the Galaxy is discussed. It is foundthat Jc/E(B-V) is significantly lower in the inter-arm region frominside the inner and outer spiral arms. The observed value of Jc/E(B-V)for HD 153919, the optical component of the binary system containing theX-ray source 2 U 1700-37, indicates a distance of at least 1.5 kpc whichsuggests that it is more luminous and massive than an ordinary O 6 star.
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Observations in linearly polarized light of the intensity of the diffuse lambda 6180 absorption band in 49 O, B, and A stars.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1973A&A....27..261G&db_key=AST
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V605 Aquilae: a Nova-Like Variable in an Old Planetary Nebula
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1971ApJ...170..547F&db_key=AST
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V605 Aquilae: an Extragalactic Supernova?
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1971ApJ...165L...7B&db_key=AST
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The space distribution and kinematics of supergiants
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1970AJ.....75..602H&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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INHABITED SKY
