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For experiments of the type A(\vec e,e'\vec p) the 3-spectrometer setup of the A1 collaboration at MAMI has been supplemented by a focal plane proton-polarimeter. To this end, a carbon analyzer of variable thickness and two double-planes of horizontal drift chambers have been added to the standard detector system of Spectrometer A. Due to the spin precession in the spectrometer magnets, all three polarization components at the target can be measured simultaneously. The performance of the polarimeter has been studied using elastic p(e,e'p) scattering.Comment: 23 pages LaTeX, 13 ps figure

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A novel K-edge imaging method has been developed at the Mainz Microtron MAMI aiming at a very efficient use of the transition radiation (TR) flux generated by the external 855 MeV electron beam in a foil stack. A fan-like quasi-monochromatic hard X-ray beam is produced from the ¦1 mrad wide TR cone with a highly oriented pyrolytic graphite (HOPG) crystal. The absorption of the object in front of a 30 mm ¢ 10 mm pn-CCD photon detector is measured at every pixel by a broad-band energy scan around the K-absorption edge. This is accomplished by a synchronous variation of the lateral crystal position and the electron beam direction which defines also the direction of the TR cone. The system has been checked with a phantom consisting of a 2.5 µm thick molybdenum sample embedded in a 136 or 272 µm thick copper bulk foil. A numerical analysis of the energy spectrum for every pixel demonstrates that data as far as ¦ 0.75 keV away from the K edge of molybdenum at 20 keV still improve the signal-to-noise ratio. Prospects are discussed to investigate the human lungs with xenon as a contrast agent at the available total primary photon flux of 2 ¢10 10 /(s¡ 0.1% bandwidth (BW)) only.