The electron linac on the basis of system with nonsynchronous waves for nuclear geophysics

Abstract

In nuclear geophysics the chinks carottage in minerals search by means of radiation occurring in ground with the presence of bremsstrahlung produced by an electron linac (Compton effect, /spl gamma/-/spl gamma/' reaction) is widely known. An induction electron linac of LIA-0,5/50 type developed in the Institute of the Electrophysical Equipment (St.Petersburg) has the greatest advancement in Russia. Such devices have a diameter of no more than 10 cm, length about 3 m, electron current up to 50 A, electron energy about 0.5 MeV and pulse duration of 50 ns. The linac, power supply system and control equipment are displaced in the same cylindrical module. The electric power is supplied through cable from a source placed on a ground surface. The signals from the control equipment are transmitted to the ground board. A lack of such a system is the rather small efficiency, that is characteristic for induction linacs, and limited service life in conditions of high temperature (up to +2000 C), caused by degradation of ferrite cores of the accelerating structure. In the report we give the results of preliminary research for an electron linac based on the autoresonant acceleration principle are described. Such linacs have certain restrictions on energy and acceleration rate, but are represented as most effective for geophysics tasks decision by specific differences of the single resonator accelerating system.