Electroformed grazing incidence x-ray mirrors for a mirror array telescope

Grazing incidence Wolter type I mirrors for higher-energy x rays have been replicated from two superpolished mandrels by electroforming. Single mirrors and a nested pair were tested with 1.5- and 6.4-keV x rays, and their subminute of arc resolution and reflectivity close to the theoretical values are confirmed. We present the design of the mandrels, mirror mounting scheme, and results of the x-ray test. The microroughnesses of the mirrors measured using an optical profilometer were compared with the x-ray test results.