THE ASTROPHYSICAL JOURNAL SUPPLEMENT SERIES 104:101-115, 1996 May

      FAR-ULTRAVIOLET STELLAR PHOTOMETRY: FIELDS CENTERED ON RHO OPHIUCHI
                            AND THE GALACTIC CENTER

                               EDWARD G. SCHMIDT
       Department of Physics and Astronomy, The University of Nebraska,
               Lincoln, NE 68588-0111; eschmidt@unlinfo.unl.edu

                                      AND

                             GEORGE R. CARRUTHERS
      E. O. Hulbert Center for Space Research, Code 7609, Naval Research
                     Laboratory, Washington, DC 20375-5320


                                   ABSTRACT

        Far-ultraviolet photometry is presented for 121 objects in a 20 deg
     diameter field centered on Rho Oph and for 649 objects in a field
     covering the Galactic center.  Broadband magnitudes with effective
     wavelengths of 1375 A and 1781 A are given.  The Galactic center field
     overlaps two fields which were discussed in an earlier paper.  Eighty-
     eight percent of the ultraviolet objects in the Rho Oph field were
     identified with visible stars using the SIMBAD database, while only 9%
     of the objects are blends of early-type stars too close together to
     separate with our resolution.  The photometric calibration was studied
     in detail, and corrections for nonlinearity were derived for the
     fields analyzed earlier as well as those discussed here.  For stars in
     common between the Galactic center field and the previous fields, a
     comparison of the magnitudes yielded estimates of the internal errors
     of the magnitudes of sigma_1375 = 0.13 mag and sigma_1781 = 0.21 mag.
     A collated list of stars in the fields covering the Galactic center
     and incorporating the revised calibration is presented and compared
     with the S201 data of the same region.  The properties of the sample
     of ultraviolet objects in the Rho Oph field are briefly commented
     upon.

     Subject headings: Galaxy: center -- ISM: individual (Rho Ophiuchi) --
                       stars: fundamental parameters -- surveys --
                       ultraviolet: stars