Transverse Optical Diagnostics For Intense Focused Heavy Ion Beams

Beam-induced fluorescence of dense gas targets has been studied for its application to measure the transverse intensity distribution of energetic focused heavy ion beams. Mechanisms of light emission are discussed on the basis of measured wavelength- and time-resolved light emission of argon. Gas pressures from 10 mbar up to 1 bar have been used. Transverse beam intensity profiles of 200 - 400 AMeV U-238 pulses from the heavy ion synchrotron SIS-18 at the Gesellschaft fur Schwerionenforschung, Darmstadt, Germany with up to 5 . 10(9) particles per pulse focused to a sub- millimeter spot have been recorded with argon and helium as target gases. Beam profiles recorded at the ArII lines by an optical filter resulted in the narrowest, most realistic beam diameters.