Application of bent crystals at IHEP 70-GeV accelerator to enhance the efficiency of its usage

V. I. Kotov, A. G. Afonin, V. M. Biryukov, Y. A. Chesnokov, N. A. Galyaev, V. N. Gres, V. A. Maisheev, V. A. Medvedev, A. V. Minchenko, V. I. Terekhov, E. F. Troyanov, Y. S. Fedotov, V. N. Zapolsky, B. A. Zelenov, Y. M. Ivanov, W. Scandale

Published 2001-10-31Version 1

Bent crystal was extracting 70-GeV protons with average intensity 4*10^11 (as measured in external beamline) per spill of 1.6 s duration, in parallel to the simultaneous work of two internal targets in the accelerator ring. An additional crystal, placed in the external beamline, was deflecting a small part of the extracted beam with intensity 10^7 protons toward another physics experiment. Crystal-extracted beam had a typical size of 4 mm by 4 mm fwhm at the end of the external beamline. Measurements for the extraction efficiency and other characteristics at the simultaneous work of four experimental set-ups are presented. With crystal working in the above-said regime during one month, no degradation of channeling was observed. The studies of extraction efficiency have been continued with new crystals.