Optimization of electrodynamic characteristics of the buncher-resonator for a free electron laser

Selection of geometric sizes of a resonator buncher comprising 1.5 accelerating cells and linking cell is performed. When selecting the inner resonator dimensions the attention is first of all paid to minimization of Er/Ez(z, γ) function in the axial region. At the same time the value of the field overstrain coefficient under a high value of effective shunt resistance is also minimized at the expense of changing the drift tube profile. 2 refs.; 2 figs.; 4 tabs