GHRS Instrument Science Report 063 "Line Spread Functions and Resolution for GHRS-LSA Spectra with COSTAR" Ronald L. Gilliland Abstract excerpted from the report: Deployment of the COSTAR mirrors for GHRS has successfully cancelled the deleterious effects resulting from spherical aberration of the HST primary mirror. Prior to COSTAR, the Large Science Aperture (LSA) line spread function (LSF) was characterized by a Gaussian core nearly twice as broad as that provided by the instrumental resolution limit with extended non-Gaussian wings. After COSTAR the LSF for the LSA is only 20-30% broader in a Gaussian core than spectra from the SSA and the extended wings are absent.
