... HST . ... Data . ... News and . ... HST Overview . Overview . ... HST Spectroscopy STIS/GHRS/FOS | ... Change of Supported Apertures for E230H Exposure Time Incorrect in Interrupted STIS Exposures CALSTIS 2.0 Released Improved Cosmic Ray Rejection Parameters for STIS New STIS Reference Files CCD Hot-Pixel Alert for STIS Spectroscopic Observations STIS Fringing Tutorial Now Available GHRS `poffsets' Task not Reliable for Weak Data FOS Paper Products Now Support Spectropolarimetry ...
... 172, Astronomical Data Analysis Software and Systems VIII, eds. D. M. Mehringer, R. L. Plante, & D. A. Roberts (San Francisco: ASP), 395 . ... We have investigated the internal zero-points of the HST's Faint object spectrograph (FOS) on-orbit wavelength calibration between 1990 (launch) and 1997 (de-commissioning). ... For BLUE systematic shifts of the zero-points are present, which amount to a maximum offset of 7 pixels (1.75 diodes) over the entire period. ...