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.
|
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.
|
Noncircular motions in the Perseus spiral arm
An examination of the motions of the optical spiral tracers in thePerseus arm reveals a clear kinematic separation between the inner andouter sides of the arm. Those objects on the inner or near side have amean velocity residual of -10.7 km/s, while those on the outer or farside have a mean positive residual of +7.0 km/s. These velocityresiduals are interpreted in terms of the linear density-wave theory asstreaming motions between the sides of the arm. Plausible solutions forthe amplitudes of the noncircular motions yielded 10 to 20 km/s and 7 to15 km/s for the radial and tangential components, respectively. Theseresults are about twice the amplitudes suggested by the theory.
|
Photographic observations of comets and minor planets
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1973A&AS...11..107J&db_key=AST
|
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
|
Spectrographic and Photometric Observations of Some Stars from the "luminous Stars in the Northern Milky way i" and "ii" Catalogues.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1963ApJ...137..547P&db_key=AST
|
Blue Giants in Cassiopea and Perseus (Spanish Title: Gigantes Azules en Casiopea y Perseo)
A list is given of 76 stars classified on objetive prism plates asbelonging to the natural group OB. The stars included in the presentlist were found on plates taken with the 26-30 inch Tonantzintla SchmidtCamera and a 4-degree objetive prism.
|
