Observation of "volume reflection" effect in crystal collimation experiments

TL;DR

This paper reports the first experimental observation of the 'volume reflection' effect in crystal collimation, demonstrating coherent beam scattering in bent crystals with heavy ions and protons at high-energy colliders.

Contribution

It provides the first experimental evidence of the 'volume reflection' phenomenon predicted in 1987, supported by detailed Monte Carlo simulations.

Findings

Observation of beam coherent scattering ('reflection') in bent crystals

First experimental evidence of 'volume reflection' effect

Simulation results align with experimental data

Abstract

Strong effect of beam coherent scattering ("reflection") in a field of bent crystal is observed in crystal collimation experiments performed with heavy ions and protons at RHIC and started at Tevatron collider. Detailed simulation using Monte Carlo code CATCH is done in order to understand the observations and relate them to the physics of beam coherent scattering in crystal. A.M. Taratin and S.A. Vorobiev predicted the effect of beam "volume reflection" in bent crystals in 1987. The presented data is the first manifestation of this new physical phenomenon in experiment.