FIRST BEAM TEST OF 81 . 5 MHZ RFQ FOR ITEP-TWAC

The 4 vane RFQ resonator with magnetic coupling windows as initial part of high-current Heavy Ion Linac for ITEP TWAC facility is presently under commissioning at ITEP. It was constructed for acceleration of ions with 1/3 charge to mass ratio to the energy of 1.57 MeV/u with beam current up to 100 mA. Additional beam dynamics simulations have been carried out for actual fields of the RFQ in order to determine both extreme output beam properties for different ion species with charge to mass ratio in the range of 1-0.25 and limitations for high-brightness of the high-current injector. The beam test of RFQ has been started with protons at relatively low electrode voltage for experimental studying the RFQ beam dynamics in the wide range of rf power operation. First results of the beam test in comparison with beam dynamics simulations are presented.