A RESIDUAL-GAS IONIZATION BEAM PROFILE MONITOR FOR THE HEIDELBERG TEST STORAGE-RING TSR

A monitoring device for the transverse density distribution of stored heavy-ion beams, based on the detection of ionization products of the beam particles in the residual gas, has been developed for the heavy-i on Test Storage Ring (TSR) in Heidelberg. With two monitor units insta lled in the ring, non-destructive, sensitive measurements of the horiz ontal and vertical profiles of cooled stored ion beams can be performe d with a spatial resolution of about +/-(0.2-0.3) mm. The beam profile monitors are used to determine the transverse beam temperature, to st udy transverse cooling and heating mechanisms, to observe the ion beam behaviour during experiments, and to determine storage-ring parameter s such as the dispersion function. The principle, technical realizatio n and operation of these devices are described. First experimental res ults concerning transverse electron cooling of heavy-ion beams are dis cussed, in particular the measurement of cooling rates and the optimiz ation of the alignment between the stored ion beam and the cooling ele ctron beam.