DEVICE FOR FAST INTERRUPTION OF ACCELERATED ION BEAM AT DC-60 AND IC-100 CYCLOTRONS

To study the optical properties of irradiated solids at the early stages of defect structure formation, there is a need to improve the time resolution of the recorded ionoluminescence and to record particles interacting with the sample with a smaller energy spread. The article describes the developed system of a fast beam chopper, which is based on deflection plates placed in the channel of the axial injection of an accelerator, immediately before the injection of the ion beam into the magnetic resonance system of the accelerator. Chopper affects the constant flow of ions in the axial injection, obtained from the ion source and injected into the accelerator and deflects it with a frequency necessary to form the required number of bunches at the exit of the accelerator. Chopper allows to obtain a beam of charged particles with different time parameters on the DC-60 and IC-100 accelerator complexes, the resonance systems of which operate in the frequency range from 11 MHz to 22 MHz and, when accelerating ions, produce particle flows at the accelerator output, grouped into bunches with a duration of about ~2…5 ns and a repetition period of ~90…45 ns. This chopper uses a fast switch of high voltage supplied to the deflection plates, at which the ion flow is deflected at the right time from injection into the accelerator, thereby ensuring effective rarefaction of the number of bunches and, accordingly, the ion flow from 100% to 1%, down to single bunches.

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