Comparative Simulation Studies of Electron Cloud Build-up for Isis and Future Upgrades

Electron cloud effects currently limit the performance of several proton accelerators operating with high beam current. Although ISIS, the 160 kW 70–800 MeV proton synchrotron at the Rutherford Appleton Laboratory (UK), has never appeared to be affected by the problem in its 20 years of operations, e-p instabilities could potentially be a cause of concern for future machine upgrades to higher beam powers. In this paper we review the present status of simulations for ISIS and compare it to preliminary results for the ongoing second harmonic upgrade and for two possible upgrade options in the future: a 0.5MW 180–800 MeV scheme and a 1MW 0.8–3 GeV scheme with an additional synchrotron using ISIS as a booster [1].