The accuracies reflect our current understanding of STIS as of May 1999 and are those we expect the pipeline calibration or recalibration of archive data to achieve during Cycle 8. The latter is frequently updated as we continue to work through the on-orbit calibration of STIS providing updated calibration reference files to the pipeline and the archive for STIS's many modes and capabilities. Due to the limited calibration-lamp lifetimes, we expect to take MAMA flats once per year per detector. As our knowledge grows, we will provide updates on the web pages. All accuracies refer to prime wavelength settings and directly calibrated special secondary settings.
Intermediate settings have roughly a factor of two less accuracy.
Assumes star is well-centered in slit. See the HST Data Handbook for a more complete description of the impact of centering on accuracies. See the HST Data Handbook for a fuller description of the impact of slit width on photometric accuracy. All accuracies refer to prime wavelength settings and directly calibrated special secondary settings. Intermediate settings have roughly a factor of two less accuracy.