SUPERCONDUCTING RF ELECTRON RECIRCULATOR FOR NUCLEAR PHYSICS RESEARCH AT LEBEDEV PHYSICAL INSTITUTE

V.G. Kurakinª¹, G.A. Sokol¹, V.G. Nedoresov², B.S. Ishkhanov³, V.I. Shvedunov³

¹Lebedev Physical Institute of Russian Academy of Sciences, Moscow, Russia

²Institute for Nuclear Research of Russian Academy of Sciences, Moscow, Russia

³Skobeltsyn Institute of Nuclear Physics, Lomonosov Moscow State University, Moscow, Russia

Abstract

Conceptual design of the superconducting rf accelerator is discussed. This machine is supposed to be used in the field of low and intermediate energy nuclear physics. Four pairs of dipole magnets at the vertexes of square and four superconducting rf linacs between them form a configuration that allows multiple electron beam acceleration from the injection to the final energy, synchronism being provided by proper orbit lengthening in bending magnets after each turn. Additional superconducting rf linac is used for injection into the main accelerator. Special design of dipole magnet makes it possible to stop recirculation in order to guide beam to experimental area. Thin target is used for experiments in order to recover beam energy. This allows to save rf energy and to provide safe radiation conditions of the accelerator as well.

Synchronism conditions as well as dipole magnet design dictate the energy gain per turn in the accelerator. For field strength about 14 kGs in dipoles the energy gain per turn is 600 MeV for TESLA type superconducting cavity (f=1.3 GHz), and the maximum electron energy 2 GeV might be realized with 3 turns. Taking into account the working accelerator gradient 25 MeV/m of TESLA type cavity the accelerator might be placed in existing accelerator hole of the high energy physics department in Troitsk where electron synchrotron to the energy 1.3 GeV is under operation now.

The main arguments in favor of accelerator schema suggested are given in the paper. Beam optics as well as recovery problems are discussed followed the appropriate beam envelope calculations.

ª – corresponding author

Paper 

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