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P.J. Serlemitsos (NASA/GSFC)
The X-ray Astrophysics Branch at the Goddard Space Flight Center is in the midst of preparing 5, 40 cm diameter, conical foil mirrors for the Astro-E mission. Three of these have already been delivered to our Japanese colleagues at the spacecraft site and are now in calibration at their X-ray beam line. The delivery of the last mirror is planned for early 1999. Design parameters, materials, assembly and tuning techniques are essentially the same for all five mirrors and not very different from those used earlier for the four mirrors on the ASCA observatory. One major difference is an improved surface preparation technique (epoxy replication versus acrylic lacquering) which has roughly halved the new PSF (point spread function). Four of the mirrors are slated for CCD focal plane detectors. They consist of 175 nested shells each, tuned to a 4.75 m focal length. They have Au reflecting surfaces. The fifth mirror has 168 nested shells tuned to a 4.5 m focal length. The surface in this case is Pt, chosen for the significant enhancement in its high energy response. Typical mirror weight is under 20 kg. Preliminary performance parameters based on ray tracing and ground calibrations will be presented.