ABSTRACT NINKOV, Zoran AST-9421606 An ongoing investigation into the star formation process has utilized the Rochester Institute of Technology 2K x 2K cooled CCD camera to image OB clusters that are at the core of associations in both the southern and northern hemispheres. These UBVRI images of the central 7' x 7' core regions have allowed study of the initial mass function to lower mass limits than previously determined. In many of these OB cores there is a central, luminous O-star, or multiple system, that dominates the brightness. From CCD images it is apparent that these central O-stars have many more companions than has been cataloged in existing double and multiple star catalogs (e.g. ADS and IDS). The brightness of the central star and the size of the point spread function results in considerable contamination of the secondary star image. Accurate multi-band photometry of the companions would allow for estimation of their spectral types and thus the mass function, and from this is a better understanding of the massive star formation process and the possible origin of runaway stars. The use of the Phillips Laboratory Starfire Optical Range to obtain high resolution images of these central stars, and their companions, in a number of OB clusters, and to permit the reduction and analyses of this data. * * *
