NEW FAR-ULTRAVIOLET INTRINSIC SPECTRAL FLUXES OF HOT STARS AND THEIR PHOTOSPHERIC TEMPERATURES

We present photometric, far-ultraviolet (FUV) intrinsic spectra of Gal actic OB stars that were acquired by the orbital Hopkins Ultraviolet T elescope (HUT) at 2-3 Angstrom resolution in the range lambda = 912-18 40 Angstrom. Flux-calibrated by observations of standard white dwarfs to 5% systematic uncertainty, and corrected for extinction to similar to 15% random uncertainty, the lightly dereddened B-star spectra agree with Kurucz-model atmospheric fluxes at most wavelengths lambda > 100 0 A. The best-fit T-eff are within 500-1000 K of T-eff-values recently derived by others with longer wavelength (lambda > 1200 Angstrom) dat a. The HUT B-star fluxes near 1000 Angstrom are systematically similar to 5% higher than the models-just within the systematic uncertainty b ut yielding FUV color temperatures that are at least 1000-5000 K hotte r than models.