Measurement of space-charge-induced frequency shifts of quadrupolar beam oscillations in the SIS

For high-intensity heavy-ion beams a non-destructive method of determining the incoherent tune shift due to space charge and thus the emittance is of practical interest. We have implemented in the SIS a method which was for the first time studied recently at LEAR [M. Chanel, Proc. European Particle Accel. Conf., Sitges, 1996, p. 1015]. In this method the coherent space-charge tune shift of quadrupolar beam-envelope oscillations is used to determine the incoherent tune shift. These frequencies are slightly shifted from 2Qh,v due to space charge. The technique and the results of these measurements will be discussed in this paper.