Crystal-Assisted Beam Extraction and Collimation at the U-70 Circular Accelerator

physics.acc-ph

/ Authors

A. G. Afonin, V. T. Baranov, S. Bellucci, S. A. Belov, S. Bini, V. N. Gorlov, G. Giannini, A. D. Ermolaev, I. V. Ivanova, D. M. Krylov

and 8 more authors

V. A. Maisheev, D. A. Savin, E. A. Syshchikov, V. I. Terekhov, V. N. Chepegin, Yu. A. Chesnokov, P. N. Chirkov, I. A. Yazynin

/ Abstract

New crystal technique - array of bent strips and a fan-type reflector, based on thin straight plates - have been used for research of extraction and collimation a circulating beam in the U-70 accelerator at the energy 50 GeV and 1.3 GeV. It is shown, that new devices can effectively steer a beam in a wide energy range. For protons with energy 50 GeV efficiency of extraction and collimation about 90 % has been achieved which is record for this method. Reduction of particle losses in 2-3 times was observed also in accelerator at application of different crystals in comparison with the usual one-stage collimation scheme of beam with a steel absorber.