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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.
| 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.
| A photoelectric UBV catalogue of 610 stars in Puppis
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1983MNRAS.205..241R&db_key=AST
| A study of galactic structure in a region of Puppis
Galactic structure and rotation in the region of the Puppis OB 1 and OB2 associations are investigated on the basis of spectrophotometric andkinematic observations. Data was obtained from measurements of platestaken at the ESO objective prism astrograph at a spectral dispersion of110 A/mm. Spectral types, B magnitudes, distance moduli andgalactocentric distances are presented for 102 stars, including 74 oftypes O5 through B3 and the remainder of types B5 and B6, and radialvelocities determined by Fehrenbach's method as well as derived circularvelocities are presented for 63 OB stars. The results demonstrate thereality of the Pup OB 1 association, which is found at a distancemodulus of 12.20 with a mean radial velocity of 37 km/sec. The physicalreality of the Pup OB 2 association, however, appears doubtful, due tothe spread of the more distant group of OB stars (distance modulus13.45, mean radial velocity 57 km/sec) over a distance of more than 3kpc; this more distant group, as well as the H II region S 311, areassigned to an extension of the Perseus arm. The galactic rotation curvederived is found to exhibit a clear rise for galactocentric distancesgreater than 12.5 kpc.
| On the nature of the PUP cluster NGC 2483.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1975A&AS...20..289F&db_key=AST
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