Hollow-Beam klystron design for the international linear collider

We describe the capabilities of an integrated software suite for the design of high-power klystrons. As an application example, the codes are applied to a 10 MW, 1.3 GHz hollow-beam klystron to meet the requirements of the International Linear Collider. The hollow-beam approach allows high beam current (140 A) in a compact package with moderate gun voltage (120 kV). The benchmark system has an interaction length of 0.92 m, 47 dB gain and 63% inherent efficiency (excluding contributions of a biased beam collector). We discuss a electron gun design to generate a narrow annular beam with relatively small axial energy spread.