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The Physics of Massive OB Stars in Different Parent Galaxies. I. Ultraviolet and Optical Spectral Morphology in the Magellanic Clouds

Walborn, Nolan R.; Kudritzki, Rolf-Peter; Lennon, Daniel J. +2 more

HST/FOS and ESO 3.6m/CASPEC observations have been made of 18 stars ranging in spectral type from O3 through B0.5 Ia, half of them in each of the Large and Small Magellanic Clouds, in order to investigate massive stellar winds and evolution as a function of metallicity. The spectroscopic data are initially presented and described here in an atlas …

Decision Trees for Automated Identification of Cosmic-Ray Hits in Hubble Space Telescope Images

Chandar, Rupali; Ford, Holland; White, Richard +2 more

We have developed several algorithms for classifying objects in astronomical images. These algorithms have been used to label stars, galaxies, cosmic rays, plate defects, and other types of objects in sky surveys and other image databases. Our primary goal has been to develop techniques that classify with high accuracy, in order to ensure that cel…

Detection, Photometry, and Completeness of FOCAS Catalogs for the HST Medium-Deep Survey

Valdes, Francisco; Griffiths, Richard E.; Neuschaefer, Lyman +1 more

We discuss the methods which we have developed and applied to optimize the detection efficiency of faint galaxies with the HST Wide Field and Planetary Cameras both prior and subsequent to the HST refurbishment mission in December 1993. Our methods are based on the FOCAS (Tyson and Jarvis 1979) automated detection software package, which we have a…