Calibration Access and Data Handbook

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Provides the transmission due to self vignetting of the RGA as a function of dispersion angle $\beta$. This is used for an analytical evaluation of the effective area. Due to the close stacking of the grating plates inside the RGA, light at large dispersion angles cannot leave the RGA assembly, and therefore, effectively the active surface of the grating plates is vignetted by the back of the neighboring plate.


Michael Smith 2011-09-20