Ulrich Bingel

Mirror system for the German x-ray satellite ABRIXAS: I. Flight mirror fabrication, integration, and testing

The tight ABRIXAS program schedule requires 250 mirror shells to be produced, checked and accepted within one year. This means that the fabrication processes have to be fully understood and kept completely under control. This applies mainly for the major production steps, like gold-coating of the mandrels, Nickel electroforming, mirror shells release from the mandrels and mirror shells testing and acceptance. We will report about the way how we tackled these technical and logistic challenges. Another important step for the optical performance of ABRIXAS Mirror Modules is the integration of the 27 mirror shells in the structural parts. This process requires high skill and good control means, like optical collimator, CCD camera and sophisticated analysis tools in order to achieve optimal-co-alignment of the 27 mirror shells axes and best confocality. This is guaranteed by dedicated test-facilities and sophisticated analyses software. We will report about the results obtained on integrated single mirrors shells as well as on the assembly of all 27 mirror shells.

Production and testing of development mandrels for Constellation-X

Two identical Wolter type 1 mandrels, with 50 cm diameter and 8.4 meter focal length, to be used by NASA/MSFC for their Constellation-X mirror development program, have been produced and tested by Carl Zeiss. In August 1999, both mandrels have been delivered to MSFC. Key optical performance of both mandrels: On-axis HEW; < 3.2 arc sec and micro-roughness: better than 0.30 nm RMS. We will report about mandrels design, fabrication, test and verification of their X-ray optical performance.