The Hermes experiment (HERa MEasurement of Spin) at Desy was designed to study the spin structureof the nucleon in semi-inclusive deep inelastic scattering. The internal structure of the nucleon has beeninvestigated in detail and it has been measured that the intrinsic quark spin contribution is only about30% of the total spin of the nucleon. A formalism to describe the internal structure of the nucleon calledGeneralised Patron Distributions (GPDs) was developed recently to understand the fundamental structure ofthe nucleon. These GPDs can be accessed by the measurement of hard exclusive reactions and hard exclusiveprocesses that can be understood in terms of GPDs. The accumulated Hermes data offer access to GPDs indifferent combinations of beam charge and beam and target helicity asymmetries.To improve exclusivity and to enhance the resolution of kinematic variables to study hard exclusive processeswhich provide access to the GPDs and hence to the orbital angular momentum of the quarks, in January2006 a Recoil Detector was installed that surrounded the internal gas target of the Hermes experiment.The Hermes Recoil Detector consisted of three components: a silicon strip detector inside the vacuum, ascintillating fiber tracker and the photon detector. All three detectors were located inside a solenoidal magnetwhich provided a 1T longitudinal magnetic field. The Recoil Detector improves the selection of exclusiveevents by a direct measurement of the momentum and track position of the recoiling particle as well as byrejecting non-exclusive background. This detector was an ideal novel tool to combine energy and positionmeasurements for charged particles in a momentum range of 0.1 to 1.4 GeV/c. The Recoil Detector wasfully commissioned and operating. Data was taken continuously until the final Hera shutdown in July of 2007.In this thesis we report on the performance of the Recoil Detector and more specificly about the scintillatingfiber tracker which was built in the Justus-Liebig Universität Giessen. Alignment run, mapping, light guidetest, gain monitoring system, pedestal stability, data quality, online monitoring and efficiency are repartedin this thesis for the scintillating fiber tracker (SFT). A preliminary analysis of exclusive Rho0 of the latestdata 07c2 was carried out to show the improvement of the selection of exclusive events with the Recoil Detector.
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