Abstract
Abstract
Transverse instability growth rates in the CERN Proton
Synchrotron (PS) are studied thanks to the recently updated
impedance model of the machine. Using this model, macroparticle
tracking simulations were performed with a new method well-suited
for the slicing of short wakes, which achieves comparable
performance to the originally implemented method while reducing the
required number of slices by a factor of 5 to 10. Furthermore,
dedicated beam-based measurement campaigns were carried out to
benchmark the impedance model. Until now, beam dynamics simulations
based on this model underestimated instability growth rates at
injection energy. Thanks to a recent addition to the impedance
model, namely the kicker magnets' connecting cables and their
external circuits, the simulated instability growth rates are now
comparable to the measured ones even when neglecting the impact of
the space charge force. Finally, the space charge force is included
in simulations and its impact on the instability growth rate and
intra-bunch motion is studied.