Developing the Optimal Technique for Cluster Photometric Redshift Determination: an Essential Ingredient in Measuring Dark Energy with Cluster Abundances. Final Report

摘要

We have evaluated two conceptual optical designs. One of these collimates the light from the telescope, and then passes it through dichroic beamsplitters. The disadvantage of this approach is the sensitivity of the optical transmission to angle of incidence, especially for 45 degree configurations. This leads to significant variation in the effective passband with position in the focal plane, and corresponding systematic errors in photometric redshifts. We have therefore adopted a different approach, in which a telecentric converging beam impinges on the beamsplitter.