SPECTROPHOTOMETRY OF FLUX CALIBRATION STARS FOR HUBBLE-SPACE-TELESCOPE

Fluxes are presented for 103 stars which were observed for Hubble Spac e Telescope (HST) calibration. Perhaps the most important aspect of th is work is confirmation of a revised zero point for optical flux calib ration of HST as described by Colina and Bohlin from synthetic photome try. Two cautions are offered for users of the Oke and Gunn spectropho tometric system, and simple corrections are suggested. The present sta rs are of interest because of their accessibility and their importance in a variety of standard systems. Included are UV and optical spectro photometric flux standards, UBVRI and IR photometric standards, and ma ny stars from the Equatorial Selected Areas for which UBVRI colors exi st as well. It is hoped that the present data will be of use to those relating results between systems. The spectra generally cover the rang e lambda lambda 4040-8800, with a nominal resolution of about 5.5 Angs trom pixel(-1). The data are referred to the absolute calibration of a lpha Lyrae recommended by Megessier. Tabular magnitude values for Haye s and Oke-Gunn wavelengths are presented. The same tables as well as m ean magnitudes within 25 Angstrom bins every 25 Angstrom in ASCII and PostScript format, and flux-calibrated spectra, may be obtained from t he author.