Hubble Space Telescope GHRS Instrument Science Report 060
GHRS Instrument Science Report 060
"GHRS Cycle 2 Sensitivity Monitoring Program 4124"
David R. Soderblom, Lisa E. Sherbert, Stephen J. Hulbert, and Claus Leitherer
Abstract excerpted from the report:
The GHRS observed the ultraviolet standard star u Col in late
September 1993 (Cycle 3) as part of a delayed Cycle 2 calibration
program. A comparison of those observations to spectra of the same
star obtained about a year earlier show that the sensitivity of
the GHRS has been stable to within better than 1%. The fluctuations
about unity of ratios of measurements obtained at different times
indicate that a single observation of a star in the LSA has an
uncertainty in its flux due to mirror centering errors of about
1.0 %. This value applies to pre-COSTAR observations.