THE IMPACT OF BEAM LOADING TRANSIENTS ON THE RF SYSTEM AND BEAM BREAKUP INSTABILITIES IN ENERGY RECOVERY LINACS

In multi-turn Energy Recovery Linacs (ERLs), the filling pattern describes the order that which bunches are injected into the ERL ring. The filling patterns and recombination schemes together can create various beam loading patterns/transients, which can have a big impact on the RF system, namely the cavity fundamental mode voltage, required RF power, and beam breakup instability. In this work, we demonstrate one can lower the cavity voltage fluctuation and rf power consumption by carefully choosing the right transient by using an analytical model and simulation