PRELIMINARY COMPARISION OF THE HST AND WHITE DWARF ABSOLUTE FLUX SCALES


              Ralph Bohlin
              Space Telescope Science Institute

              Instrument Science Report on Standard Calibration Sources 002
              December 1993


ABSTRACT

As part of an ongoing effort to develop a set of standard stars with accurate
absolute spectrophotometry from 1050 to 10000A, the FOS flux spectrum for
G191B2B (WD0501+527) is divided by a model spectrum for the case of a pure
hydrogen atmosphere to derive the difference between the current HST flux scale
and the flux scale defined by the physics of model atmosphere calculations.
Figure 1 and the Appendix specify the conversion function.