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For the Time Reversal Invariance experiment at COSY (TRIC) that had been proposed at the Forschungszentrum Jülich a novel technique for measuring total cross sections in internal experiments was developed and the achievable precision of this measuring technique was tested. The experimental idea constitutes a true P-even T-odd null test of TRI. In order to compare to the theoretical upper bound from edm measurements (Haxton and Höring, Nucl Phys A560:469, 1993), the TRI violating observable A y, xz in proton-deuteron forward scattering has to be measured with an accuracy of 10 − 6. An internal TRI experiment can determine the total cross section via the optical theorem by measuring the forward scattering amplitude. In contrast to external experiments, the only calibrated device that is needed is a precise beam current transformer (BCT). The feasibility of an internal TRI experiment was tested at COSY in a measurement of A y, y in p-p scattering, since these values are known. The analysis of the data showed the presence of unexpected large 1/ f noise contributions, which eventually reduced the achievable accuracy by a factor 3. The origin of the 1/ f noise was traced and found to be the Barkhausen noise from the ferrite-core of the BCT. A global weighted fitting technique based on a modified Wiener-Khinchin method was applied to suppress the influence of the 1/ f noise. [ABSTRACT FROM AUTHOR]

A scintillating fibre hodoscope was developed for application in a high rate environment such as the central region of external beam experiments. It accommodates rates of several 106 s−1 per fibre channel while maintaining a time resolution of about 400 ps. Its central elements are highly efficient radiation-hard scintillating fibres and a photomultiplier tube capable of operating at such rates without appreciable loss of signal amplitude. [Copyright &y& Elsevier]

The design and operation of an online energy and spatially resolving detector based on three different scintillators for laser-driven protons are described. The device can be used for a multi-Hertz recording rate. The spatial resolution is <0.5 mm, allowing to retrieve details of the proton beam which is of interest, e.g., for radiographic applications. At the same time, the particle energy is divided into three energy bands between 1 MeV and 5 MeV to retrieve the proton energy spectrum. The absolute response of the detector was calibrated at a conventional proton accelerator. [ABSTRACT FROM AUTHOR]

Abstract: Diffusion of implanted 57Co in ZnO has been determined in the temperature range 660–950°C using the modified radiotracer technique. The diffusion was found to follow the Arrhenius type relation with an activation enthalpy of (2.9±0.3)eV and a pre-exponential factor of 3×10−4 m2/s. Supported by diffusion data and conclusions provided in the literature, it is proposed that cobalt diffuses substitutionally in ZnO. [Copyright &y& Elsevier]