... HST . ... HST Overview . ... Changing Programs & Resolving Problems . ... Reference Information on Instrument Performance The following table summarizes the useful wavelength range for each of the first-order gratings of GHRS. ... The following figures illustrate the resolving power as measured for each of GHRS' gratings. ... The nominal design specification for the GHRS was R = 20,000 for the first-order gratings, but in fact one can exceed a resolving power of 25,000 at virtually all wavelengths. ...

Next: Order Definition Up: Echelle Reduction Method Previous: Retrieving demonstration and . ... That is the mapping between the space wavelength, spectral order and the space sample x , line y in the raw image. ... Sections and describe the solution of this mapping. The second step in the reduction, described in Section , is to estimate the image background. ... In the rest of this Section the algorithms used in each step of the reduction are described. ...

ST-ECF Instrument Science Report WFC3-2005-07 Ground tests of the WFC3 NIR grisms S. S. Larsen, H. Bushouse, J. R. Walsh March 2005 ABSTRACT The fundamental parameters of a slitless dispersing element are the geometrical configuration of the spectral orders, the dispersion relation relating pixel offset to wavelength and the sensitivity of each order. Based on thermal vacuum tests, the performance of the WFC3 near-IR G102 and G141 grisms has been assessed. ... WFC3 IR Grism Modeling and Rotations. ...

XMM-Newton Science Analysis System Page: 1 rgscombine August 16, 2005 Abstract Combines a list of spectrum les to create one combined spectrum le, and the corresponding list of response matrices and background spectrum, to create one nal response matrix and background spectrum le, for a paticular RGS instrument and spectral order. ... A list of response matrix les, as produced by rgsrmfgen or rgsproc. A list of background spectrum les as produced by rgsspectrum or rgsproc for TOTAL spectra. ...