Dechanneling of high energy particles in a long bent crystal

Experimental results on deflection of a 180 GeV/c pi(+)-meson beam by a 23 mm long bent silicon crystal are analyzed to study the dechanneling process of particles due to multiple scattering. A new approach for the determination of contributions from atomic nuclei and electrons to the multiple scattering using the experimental data for random crystal orientations is suggested. The results of simulations performed using this approach, in which the contribution from atomic electrons is considered according to the prescription of Bethe, are in a good agreement with the experiment.