Measurements of Emittance and Tune Spread at Linac2 and Linac4 Injection Energies for the Proton Synchrotron Booster (PSB)

The effect of space charge on the proton beam as a function of energy has been studied in the PSB. This work is part of the preparations for the connection of Linac4 to the PSB involving H- charge-exchange injection compared to the current Linac2 multi-turn injection. In the current injection process, an important fraction of the injected beam is lost after injection, and this study should help in understanding the part that is due to space charge effects, and thus give indications on the expected improvement with the new Linac4 injection. In this note, measurements of emittance and calculations of tune spread at a range of energies on a specially prepared magnetic cycle are presented. The effect of crossing the half-integer resonance is also discussed.