Calibration of the AXAF-HRC UV/ion shields at Osservatorio Astronomico DI Palermo G.S. Vaiana: II - x-ray transmission measurements
X-ray transmission measurements have been conducted at the XACT facility on baseline design AXAF-HRC UV/ion shield using an electron impact x-ray source, a transmission grating monochromator and gas flow proportional counters. Transmission has been measured at several energies in the range 0.1 - 2.0 keV with and without the transmission grating monochromator. It turns out that the monochromator enormously improves the measurement accuracy. UV measurements conducted by us on the same shield and reported elsewhere showed an unexpectedly high UV transmission which led to a redesign of the UV/ion shields. Calibration of the new shields, based on different materials, is still in progress. In this paper we outline the calibration procedure and the data analysis technique, and report transmission results on the baseline design shield.