THE S-BAND 1.6 CELL RF GUN CORRELATED ENERGY SPREAD DEPENDENCE ON π AND 0 MODE RELATIVE AMPLITUDE

摘要

The π mode or accelerating mode in a 1.6 cell rf gun is normally the only mode considered in rf gun simulations. However, due to the finite Q there is a small but measurable 0 mode present even at steady state. The π mode by definition has a 180° phase shift between cells but this phase shift for the total field is several degrees different. This results in a correlated energy spread exiting the gun. A comparison of simulation and experiment will be shown.