About multiple scattering of high energy protons in crystal deflectors

NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS

卷:355

Article; Proceedings Paper

Taratin, A. M.¹  Scandale, W.^2,3,4 

[1] Joint Inst Nucl Res, Moscow 141980, Russia

[2] CERN, European Org Nucl Res, CH-1211 Geneva 23, Switzerland

[3] Univ Paris 11, LAL, Orsay, France

[4] Ist Nazl Fis Nucl, Sez Roma, I-00185 Rome, Italy

关键词: Crystal;    Channeling;    Multiple scattering;   

DOI  :  10.1016/j.nimb.2015.02.036

来源: Elsevier

【 摘 要 】

The process of multiple scattering of high energy protons in a silicon crystal at its amorphous orientation was studied by simulation of proton trajectories in the model of binary collisions and by a straight simulation of the sequences of proton collisions with atoms when their impact parameters are randomly and uniformly distributed on the symmetry cell for a given crystallography direction. The value of the RMS deflection of multiple scattering obtained by the simulation is in a good agreement with the experiment and more than 15% larger than it follows from the Moliere theory. The obtained RMS deflection used in the Gaussian approach of multiple scattering well describes dechanneling of protons in the frame of the planar potential model. Different number of proton collisions with atoms occurs along the same crystal length for different crystal orientations. However, the change of the collision number is compensated by the corresponding change of the mean square deflection in a single collision. Therefore, multiple scattering is the same for different crystal orientations. The generator of multiple scattering for amorphous crystal orientations was proposed. (C) 2015 Elsevier B.V. All rights reserved.

【 授权许可】

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