Determining beam parameters in a storage ring with a cylindrical hodoscope using elastic proton-proton scattering

The EDDA-detector at the cooler-synchrotron COSY/Julich has been operated with an internal CH2 fiber target to measure proton-proton elastic scattering differential cross-sections. For data analysis knowledge of beam parameters, like position, width and angle, are indispensable. We have developed a method to obtain these values with high precision from the azimuthal and polar angles of the ejectiles only, by exploiting the coplanarity of the two final-state protons with the beam and the kinematic correlation. The formalism is described and results for beam parameters obtained during beam acceleration are given. (c) 2005 Elsevier B.V. All rights reserved

Radiation damage of polypropylene fiber targets in storage rings

Thin polypropylene fibers have been used for internal experiments in storage rings as an option for hydrogen targets. The change of the hydrogen content due to the radiation dose applied by the circulating proton beam has been investigated in the range 1 X 10(6)- 2 x 10(8) Gy at beam momenta of 1.5-3 GeV/c by comparing the elastic pp-scattering yield to that from inelastic p-carbon reactions. It is found that the loss of hydrogen as a function of applied dose receives contributions from a fast and a slow component. (c) 2005 Elsevier B.V. All rights reserved