A large number of mirror shells are required for the European
Space Agency's XMM telescope three mirror modules, each of which
consists of 58 thin walled highly nested Wolter I mirrors. The specified
performance of the XMM mirror modules requires new design concepts
and application of new technologies for the production of the lightweight
mirror shells. Under an ESA contract, Carl Zeiss is leading a European
industrial/scientific consortium to develop technologies that allow production
of real size XMM mirror shells by a dedicated metal/epoxy resin
replication technique. In late 1988 the first full size XMM mirror shell was
successfully replicated, having the following characteristics: total length
600 mm, maximum shell diameter 400 mm, carrier material/thickness
graphite-epoxy/0.8 mm, replication layers gold/epoxy, and total replicated
mirror surface 7500 cm2. The development, preparation, and mirror shell
replication are described, and the first results of the performance of the
mirror shell after measurements and x-ray testing are presented.
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