New Estimates of the Solar-Neighborhood Massive Star Birthrate and the Galactic Supernova Rate
The birthrate of stars of masses >=10 Msolar is estimatedfrom a sample of just over 400 O3-B2 dwarfs within 1.5 kpc of the Sunand the result extrapolated to estimate the Galactic supernova ratecontributed by such stars. The solar-neighborhood Galactic-plane massivestar birthrate is estimated at ~176 stars kpc-3Myr-1. On the basis of a model in which the Galactic stellardensity distribution comprises a ``disk+central hole'' like that of thedust infrared emission (as proposed by Drimmel and Spergel), theGalactic supernova rate is estimated at probably not less than ~1 normore than ~2 per century and the number of O3-B2 dwarfs within the solarcircle at ~200,000.
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Catalog of Galactic OB Stars
An all-sky catalog of Galactic OB stars has been created by extendingthe Case-Hamburg Galactic plane luminous-stars surveys to include 5500additional objects drawn from the literature. This work brings the totalnumber of known or reasonably suspected OB stars to over 16,000.Companion databases of UBVβ photometry and MK classifications forthese objects include nearly 30,000 and 20,000 entries, respectively.
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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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Determination of R_V towards galactic O stars
We present new measurements of the interstellar reddening parameterRV=AV/E(B-V) towards 35 O stars. The results arecombined with measurements from the literature for 60 stars to study thebehaviour of RV with heliocentric distance. RV isthe single basic parameter which characterizes the interstellarextinction from the near-infrared to the far-UV spectral region. Theabsolute extinction AV, from which RV is derived,is best determined by optical and near-infrared photometry (Cardelli etal. \cite{r3}). We consider important the derivation of RVwith the same technique in the direction of as many as possible galacticO stars.
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Five-colour photometry of OB-stars in the Southern Hemisphere
Observations of OB-stars, made in 1959 and 1960 at the Leiden SouthernStation near Hartebeespoortdam, South Africa, with the VBLUW photometerattached to the 90 cm light-collector, are given in this paper. They arecompared with photometry obtained by \cite[Graham (1968),]{gra68}\cite[Walraven & Walraven (1977),]{wal77} \cite[Lub & Pel(1977)]{lub77} and \cite[Van Genderen et al. (1984).]{gen84} Formulaefor the transformation of the present observations to those of\cite[Walraven & Walraven (1977)]{wal77} and \cite[Lub & Pel(1977)]{lub77} are given. Table 4 is only available in electronic format the CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) orvia http://cdsweb.u-strasbg.fr/Abstract.html
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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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Interstellar Extinction from 0.35 to 2.2 Microns: A Study Based on Luminous Southern Stars
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1995ApJS..101..335H&db_key=AST
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A spectroscopic database for Stephenson-Sanduleak Southern Luminous Stars
A database of published spectral classifications for objects in theStepenson-Sanduleak Luminous Stars in the Southern Milky Way catalog hasbeen compiled from the literature. A total of 6182 classifications for2562 stars from 139 sources are incorporated.
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A study of reddened luminous stars in the southern Milky Way. IV. JHK photometry.
Not Available
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A study of reddened luminous stars in the southern Milky Way. III. VRI photometry.
Not Available
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A study of reddened luminous stars in the southern Milky Way. II. H-beta photometry, reddening and distances.
Not Available
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A study of reddened luminous stars in the southern Milky Way. UVBY photometry.
Not Available
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UBV photometry of OB+ stars in the southern Milky Way
One thousand two hundred and twenty six new observations are combinedwith previously published results of the author to yield an internalyconsistent set of magnitudes and colors on the international UBV systemfor 666 stars classified as OB+ in the Stephenson-Sanduleak OB starsurvey. The U - B, B - V diagram indicates that these stars consistprimarily of O-type stars and early B-type supergiants, reddened by upto E(B - V) = 2.1 mag.
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UBV-/H-beta/ photometry of luminous stars between L equals 335 deg and L equals 6 deg
Results are reported for photoelectric UBV and H-beta photometry of 316luminous OB stars and early-type supergiants in the region between 335and 6 deg galactic longitude. UBV magnitudes for the 316 stars and betaindexes for 37 of them are presented. Absolute magnitudes, distances,and color excesses are determined for the 161 stars with measured betaindexes or known MK spectral types. The results are discussed in termsof the spiral structure of the Galaxy. From the data obtained forprogram stars assumed to be cluster members, distances are derived forthe open clusters NGC 6167 (1.7 kpc), NGC 6193 (1.3 kpc), Hogg 22 (2.0kpc), NGC 6231 (1.9 kpc), and Tr 27 (1.6 kpc).
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Finding list and spectral classifications for southern luminous stars.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1976AJ.....81..225M&db_key=AST
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INHABITED SKY
