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.
@article{arxiv.1102.2711,
title = {Crystal-Assisted Beam Extraction and Collimation at the U-70 Circular Accelerator},
author = {A. G. Afonin and V. T. Baranov and S. Bellucci and S. A. Belov and S. Bini and V. N. Gorlov and G. Giannini and A. D. Ermolaev and I. V. Ivanova and D. M. Krylov and V. A. Maisheev and D. A. Savin and E. A. Syshchikov and V. I. Terekhov and V. N. Chepegin and Yu. A. Chesnokov and P. N. Chirkov and I. A. Yazynin},
journal= {arXiv preprint arXiv:1102.2711},
year = {2011}
}