Parameterization technique for the preliminary gun design of the EU 170GHz 1MW conventional cavity gyrotron for ITER

A preliminary gun design for the EU 170 GHz, 1 MW conventional cavity gyrotron, for the TE32,09 mode [1], will be presented. The ASG magnet of the EU 170 GHz, 2 MW coaxial cavity gyrotron for ITER is used for the required magnetic field. A parameterization of the diode gun has been defined. Using the Ariadne++ code [2] the geometry has been optimized with respect to several criteria, such as the small velocity spreads, the acceptable width of the beam radius at the cavity, etc. The neutralization effect has been taken into account using a simple model.