SSN/3.1
Starlink Project
Starlink System Note 3.1
William Lupton
22nd December 1989
The ECH Echelle Spectrograph Model Package
ECH_BLOCK— BLOCKDATA to initialise spectrograph configuration
ECH_COLLIMATOR— Determine which collimator to use at a given wavelength
ECH_DISP— Determine the dispersion in mm for a given wavelength
ECH_FORMAT_CENTRE— Determine the appropriate spectrograph settings
ECH_FRSPR— Determine the free spectral range in Angstroms
ECH_INIT— Initialise COMMON blocks for a specified instrument combination
ECH_LOAD— Load COMMON blocks describing spectrograph parameters
ECH_ORDERNUM— Determine the order number of a specified wavelength
ECH_PRISMPOS— Determine the optimal prism rotation and position
ECH_REFINDEX— Determine the refractive index of fused silica
ECH_SLITANGLE— Determine the optimum slit angle
ECH_WAVECEN— Determine the central wavelength of the order
ECH_WCENTRAL— Determine the central wavelength in Angstroms
ECH_XDISPFS— Determine the cross-dispersion in mm for a given wavelength