Influence of incoherent scattering on stochastic deflection of high-energy negative particle beams in bent crystals

TL;DR

This paper studies how incoherent scattering affects the stochastic deflection of high-energy negative particles in bent crystals, revealing a maximum deflection angle linked to the crystal's curvature, which differs from positive particles.

Contribution

It introduces the concept of a maximum deflection angle for negative particles due to incoherent scattering, unlike positive particles where deflection can be increased indefinitely.

Findings

Existence of a maximum deflection angle for negative particles

Optimal crystal curvature for maximum deflection

Incoherent scattering significantly influences negative particle dynamics

Abstract

An investigation on stochastic deflection of high-energy negatively charged particles in a bent crystal was carried out. On the basis of analytical calculation and numerical simulation it was shown that it exists a maximum angle at which most of the beam is deflected. The existence of a maximum, which is taken in the correspondence of the optimal radius of curvature, is a novelty with respect to the case of positively charged particles, for which the deflection angle can be freely increased by increasing the crystal length. This difference has to be ascribed to the stronger contribution of incoherent scattering affecting the dynamics of negative particles that move closer to atomic nuclei and electrons. We therefore identified the ideal parameters for the exploitation of axial confinement for negatively charged particle beam manipulation in future high-energy accelerators, e.g., ILC or muon colliders.