The Carina Spiral Feature: Strömgren-Hβ photometry approach. I. The photometric data-base
A data-base collating all uvbybeta photometry available at present forO-B9 stars brighter than 10th visual magnitude in the field of theCarina Spiral Feature is presented. The completeness and homogeneity ofthe data-base are discussed.Based on CDS data.Table 1 is only available in electronic form at the CDS via anonymousftp to cdsarc.u-strasbg.fr (130.79.128.5) or viahttp://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/410/523
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Light Curve Solution of HD 93205 (O3 V+O8 V) Containing the Earliest Known Star in a Well-studied Binary
We present the results of an extensive photometric study of the O3 V+O8V binary HD 93205 (P~=6.08d, e=0.46). The primary O3 V star has by farthe earliest known spectral type of a normal star in a cataloged closebinary. Some 186 individual differential observations, each of precision~0.003 mag, were obtained over a contiguous interval of ~3 months in anarrow, visual-continuum bandpass. The amplitude of photometricvariability is very low, about 0.02 mag, with most of the light changesoccurring near periastron passage. Analysis of the light variations witha state-of-the-art binary model in an eccentric orbit leads to theconclusion that the system does not exhibit eclipses. Rather, the lightvariations are due mainly to orbital revolution of tidally distortedstars. However, there is an additional very small, but real, systematicdecreasing trend in the light curve of the system approximately centeredon the apastron passage, i.e., between orbital phases 0.35 and 1.0,which cannot be accounted for with present models. A nonuniformbrightness distribution on the surface of the star(s), whose originremains a mystery, may be responsible for this effect. Another plausibleexplanation of the trend may be related to turbulent viscosity, causingtidal lag. Despite this problem, one can estimate the range of possiblevalues for the orbital inclination angle, e.g., at the 5% significancelevel, 75deg>=i>=35deg, which leads to themasses MO3~=32-154 Msolar andMO8~=14-68 Msolar. The best-fit value,i=60deg, yields MO3=45 Msolar andMO8=20 Msolar. The latter value is compatible withthe reliable masses of the two O8 V stars (22 Msolar) in thedetached eclipsing binary system EM Car. This would imply that at leastone of the earliest known main-sequence O3 stars has relatively modestmass, compared to evolutionary masses of the most massive stars, whichare claimed elsewhere in the literature to reach up to at least 100Msolar.
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An Unusual Brightening Of Eta Carinae
HST/Space Telescope Imaging Spectrograph data show that the apparentnear-UV, visual-wavelength, and near-IR brightness of η Carincreased by a factor of two during 1998. Meanwhile its Homunculusejecta nebula brightened by about 30%, the largest fluctuation of thistype in the past 40 years. These developments were quite unexpected andare not easy to explain. Some dust has probably been destroyed, whilethe star's luminosity may have increased even though it was alreadyclose to the Eddington limit. Such a rapid luminosity change would be atruly remarkable phenomenon, not predicted by existing models.
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Stromgren and Hβ photometry of OB stars in the region of the Carina Spiral Feature
Stromgren and Hβ photometry of 130 stars in the Carina section ofthe Milky Way is presented. The color excesses and the distances of allstars are obtained. A good agreement is found between the CM and HRdiagrams and the spatial distribution of these stars. Tables 1, 2, 4 and5 are only available in electronic form at the CDS via anonymous ftp to130.79.128.5 or via http://cdsweb.u-strasbg.fr/Abstract.html
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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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Ubvy-Beta Photometry of 100 Stars in the Region of Eta-Carinae
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1994MNRAS.269..857S&db_key=AST
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On the extinction law in the Carina nebula
Using the results of observations of the Carina nebula made with thespace telescope Glazar, it is shown that the extinction law for thenebula is abnormal and that there is a single OB star complex within thenebula at a distance of about 2200 pc. It is suggested that the observeddistribution of OB stars in the nebula and also the appearance of thenebula itself is due to a specific structure of the absorbing cloudswithin the nebula, and that the absorbing clouds may have such structureas a result of an explosion in the center of the nebula.
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A system of OB stars in the Carina nebula.
Not Available
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An Einstein Observatory SAO-based catalog of B-type stars
About 4000 X-ray images obtained with the Einstein Observatory are usedto measure the 0.16-4.0 keV emission from 1545 B-type SAO stars fallingin the about 10 percent of the sky surveyed with the IPC. Seventy-fourdetected X-ray sources with B-type stars are identified, and it isestimated that no more than 15 can be misidentified. Upper limits to theX-ray emission of the remaining stars are presented. In addition tosummarizing the X-ray measurements and giving other relevant opticaldata, the present extensive catalog discusses the reduction process andanalyzes selection effects associated with both SAO catalog completenessand IPC target selection procedures. It is concluded that X-rayemission, at the level of Lx not less than 10 exp 30 ergs/s, is quitecommon in B stars of early spectral types (B0-B3), regardless ofluminosity class, but that emission, at the same level, becomes lesscommon, or nonexistent, in later B-type stars.
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Narrow band multicolor photometry of reddened and unreddened early-type stars
Photometric measurements and interstellar extinction curves of reddenedand unreddened early-type Southern Hemisphere stars are presented. It isshown that a number of shallow features exist in the extinction curvesrelative to a straight-line approximation.
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Observations of a region of the Carina OB 1 association using the "Glazar" space telescope.
Not Available
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Walraven photometry of nearby southern OB associations
Homogeneous Walraven (VBLUW) photometry is presented for 5260 stars inthe regions of five nearby southern OB associations: Scorpio Centaurus(Sco OB2), Orion OB1, Canis Major OB1, Monoceros OB1, and Scutum OB2.Derived V and (B - V) in the Johnson system are included.
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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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The local system of early type stars - Spatial extent and kinematics
Published uvby and H-beta photometric data and proper motions arecompiled and analyzed to characterize the structure and kinematics ofthe bright early-type O-A0 stars in the solar vicinity, with a focus onthe Gould belt. The selection and calibration techniques are explained,and the data are presented in extensive tables and graphs and discussedin detail. The Gould belt stars of age less than 20 Myr are shown togive belt inclination 19 deg to the Galactic plane and node-lineorientation in the direction of Galactic rotation, while the symmetricaldistribution about the Galactic plane and kinematic properties (purecircular differential rotation) of the belt stars over 60 Myr oldresemble those of fainter nonbelt stars of all ages. The unresolveddiscrepancy between the expansion observed in the youngest nearby starsand the predictions of simple models of expansion from a point isattributed to the inhomogeneous distribution of interstellar matter.
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Uvby-Beta Photometry of Equatorial and Southern Bright Stars - Part Two
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1980A&AS...42..311H&db_key=AST
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Photoelectric measures of the hydrogen lines in early-type stars.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1974MNRAS.169..171F&db_key=AST
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The OB stars in Carina-Centaurus
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1969MNRAS.143..273F&db_key=AST
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Radial velocities of Southern B stars determined at the Radcliffe Observatory.
Not Available
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The Brightening of η Carinae
Not Available
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INHABITED SKY
