For the current x-ray spectroscopy program at the ESR storage ring (GSI-Darmstadt) a position sensitive germanium detector system has been completed. The position sensitive structure of the detector has been realized on an area of 47 × 23.4 mm{sup}2 by an array of 200 strips (200 μm wide and 23.4 mm long) separated by 35 μm wide grooves etched through boron implanted contact. The thickness of the detector inclusive a 0.6 mm thick Li-diffused rear contact amounts to 4.1 mm. Each strip has been joined to a preamplifier placed outside the cryostat with printed leads inside the flexible Kapton foil. The energy resolution of the strips has been about 1.8 keV [FWHM] for 60 keV photons. Coincidences between neighboring strips were measured whereby a time resolution of 70 ns [FWHM] was obtained. First preliminary results obtained with the detector mounted at the transmission x-ray spectrometer FOCAL demonstrated that an energy resolution better than 100 eV is achievable together with high detection efficiency. Along with a new kind of x-ray spectrometer this detector may play a keyrole for the next step of high precision x-ray experiments, aiming on a precise test of quantum electrodynamics in the heaviest one-electron systems such as a hydrogenlike uranium.
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