A POLARIZED ELECTRON TARGET FOR A HIGH-ENERGY MUON BEAM POLARIMETER

A special magnet designed to saturate at 2.2 T a 2.7 mm thick, 180 mm wide and 588 mm long rectangular iron foil has been built in Saclay fo r the CERN SMC experiment muon beam polarimeter. It consists of an H i ron yoke equipped with two magnetizing copper coils operated in a puls ed mode in order to periodically invert the foil magnetization. The op eration point and the demagnetizing factor influence are discussed. Th e measurements with a search coil of the resulting flux density and th e influence of the eddy currents are presented. The magnet fringe fiel d which affects particle trajectories has also been measured.