Calibrating Echelle Spectra using Instrument Models
نویسندگان
چکیده
We have developed a generic model of echelle spectrographs, based on first optical principles, fully treating 3-dimensions. The geometrical part of it is capable of predicting detector positions for wavelength calibration spectra within 0.2 pix (1 sigma), solely using engineering parameters such as focal lengths, grating constants and configuration angles. First results are also available from the modeling code for grating efficiencies (blaze functions) for any given polarization, surface accuracy and random or periodic groove errors. Combined these tools allow one to carry calibrations of well observed modes into less well or even uncalibrated modes of operation.
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