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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Interstellar Extinction Along the Camelopardalis and Perseus Border
Interstellar extinction in a ~ 100 sq. degree area at theCamelopardalis and Perseus border is investigated. The study is basedon the results of photoelectric photometry of 455 stars in theseven-color Vilnius photometric system published earlier. The nearest100 stars with Hipparcos parallaxes show that the extinction starts togrow at a distance of 110--150 pc. At a distance of 1 kpc theextinction A_V is within 1.2 and 2.4 mag. At larger distances theextinction determination is affected by the limiting magnitude effect.At distances >1.5 kpc a number of O--B stars with the extinctionsbetween 2 and 4 mag are found.
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Photometry and Classification of Stars Along the Camelopardalis and Perseus Border
Seven-color photometry in the Vilnius system for 309 stars down to 12.5mag in the area along the galactic equator near the Camelopardalis andPerseus border is presented. Photometric spectral and luminosity classesof the stars are determined.
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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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An optical spiral arm beyond the Perseus arm
In the second galactic quadrant, optical spiral arm tracers have beencollected in a systematic literature search. A uniform reduction of thedata led to the detection of a distinct structure (probably a spiralarm) beyond the Perseus arm that is separated by a statisticallysignificant gap from the latter.
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A library of stellar spectra
Spectra for 161 stars having spectral classes O-M and luminosity classesV, III, and I have been incorporated into a library available onmagnetic tape. The spectra extend from 3510 to 7427 A at a resolution ofabout 4.5 A. The typical photometric uncertainty of each resolutionelement in the spectra is on the order of 1 percent while broad-bandvariations are smaller than 3 percent. Potential uses for the libraryinclude population synthesis of galaxies and clusters, tests of stellaratmosphere models, spectral classification, and the generation of colorindices having arbitrary wavelength and bandpass.
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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 measures of the 4430 A diffuse interstellar band
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1963MNRAS.125..141W&db_key=AST
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Studies in Galactic STRUCTURE.II.LUMINOSITY Classification for 1270 Blue Giant Stars.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1955ApJS....2...41M&db_key=AST
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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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A Finding List of O and B Stars of High Luminosity.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1951ApJ...113..141N&db_key=AST
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INHABITED SKY
