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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Secondary standard stars for UVBY beta CCD photometry
Accurate standard uvby indices are presented for 73 southern B, A, F andG stars in the $V$ magnitude range 8.2 to 10.9. They cover all threetransformation regions of the $uvby$ system (Olsen \cite[1983]{Olsen1})well. Standard $\beta$ indices are included for the 55 B, A, and F starsin the sample. Our results provide a useful set of secondary standardsfor uvby beta CCD photometry with southern hemisphere 1-2 m classtelescopes. A critical comparison with published photometry, in generalbased on fewer observations, is given. Based on observations made at theEuropean Southern Observatory, La Silla, Chile. Tables 3, 4, 5 are alsoavailable in electronic form at the CDS via anonymous ftp tocdsarc.u-strasbg.fr (130.79.128.5) or viahttp://cdsweb.u-strasbg.fr/Abstract.html
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Uvby-Beta Photometry of E-Region Stars
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1993A&AS..102..637J&db_key=AST
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Secondary UVBY standards in the Harvard E-regions
Photoelectric uvby photometry for 201 stars which are already UBV (RI)cstandards is presented. The photoelectric data are closely tied to theCousins uvby standards and the stars should be suitable for use asfainter (7-11 mag) secondary standards.
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UBV (RI)c standard stars in the E- and F-regions and in the Magellanic Clouds - a revised catalogue.
Not Available
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HD 47147 - A small-amplitude extreme metal-poor RRab pulsating variable
The photometric variations and physical and kinematical properties of HD47147, a ninth magnitude metal-deficient star, are discussed. The longperiod (0.79732 days), the small amplitude (0.17 mag in the visualband), and the mean effective temperature of 6160 K of this RR Lyraepulsating variable can be understood by its location near the red edgeof the instability strip. The extreme Population II characteristics ofHD 47147 are confirmed by its kinematical properties. The temperatureand the relatively high luminosity derived are consistent with bothpossibilities that HD 47147 is a red horizontal branch star or that itis a suprahorizontal branch star actually evolving redward toward theasymptotic branch. Its low amplitude suggests the possibility that thered edge of the instability strip corresponds to a smooth transitionfrom variable to non-variable stars.
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UBV photometry of E region standard stars of intermediate brightness
Photometry data are given for 335 stars in the nine E regions.Observations were made using a photometer and filters on the 47 cmreflector at Cape Town. The stellar dispersions are summarized. Data arepresented in tabular form.
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Up-To UBVRI Values for the E-Region Standard Stars
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1981A&AS...46....7V&db_key=AST
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Photoelectric standards of intermediate brightness in the E-regions. I. UBV photometry.
Not Available
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Photometric standard stars for the UBV and (RI)KC systems.
Not Available
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Fainter Standards for VRI Photometry in the E Regions
Not Available
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Standard magnitudes in the E regions.
Not Available
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