350 MHZ, 200 KW CW multiple beam inductive output tube

Summary form only given.Calabazas Creek Research, Inc. (CCR) and Communications & Power Industries, LLC (CPI) are assembling a 350 MHz, 200 kW CW, multiple beam inductive output tube (MBIOT)1. The MBIOT will be a new, high power, RF source for accelerators and colliders. This device will be a candidate RF source for the Advanced Photon Source at Argonne National Laboratory. The target efficiency is 70% with a predicted gain exceeding 22 dB. The MBIOT uses seven standard IOT electron guns arrayed in a circular pattern about the device axis. These seven electron guns all drive the same fundamental mode output cavity. The RF power is extracted through a single coaxial waveguide on the axis of the device. A solenoidal magnetic field confines the electron beam in the output cavity. CCR Designers use a number of codes for IOT design, including Beam Optics Analyzer, MAGIC 2D/3D, TRAK, HFSS, and TESLA. Design of IOT guns is particularly challenging due to the temporal nature of the electron pulses extracted from the cathode. A resonant cavity drives a control grid to extract pulses of electrons from the cathode at the design frequency. The electrons experience a different accelerating voltage depending on the phase of the RF signal. This causes both pulse bunching and debunching in the acceleration region. This must be considered to accurately predict the device performance. It is anticipated that the assembly will be completed by May 2011. The tube will be transferred to Argonne National Laboratory for high power testing. This presentation will describe the electrical and mechanical design as well as issues arising from the assembly. Any test results will also be presented.