Joint AB and LHC Project Seminar: Observations of Proton Reflection on Bent Crystals at the CERN-SPS

by Scandale, Walter (CERN (AT-DHO))

Thursday 15 Mar 2007, 14:15 → 15:15 Europe/Zurich

AT Auditorium (CERN)

We report observations, performed by the H8-RD22 Collaboration, of the so-called volume reflection effect with 400 GeV/c protons interacting with bent Silicon crystals in the H8 beam line at the CERN SPS. The volume reflection is closely related with particle channeling. This phenomenon occurs at the tangency point of a particle trajectory with the bent crystalline planes and consists in the reversal of the transverse component of the particle momentum. The measurements were collected with a high spatial resolution detector mainly based on Silicon strips. The proton beam was deviated in the direction opposite to that of channeling by ~10murad, which is ~1.3 times the critical angle, with an efficiency larger than 97% in a range of the proton-to-crystal incident angle as large as the bending angle of crystallographic planes. This evidence opens new perspectives for manipulation of high-energy beams, e.g., for collimation and extraction in the new-generation of hadron colliders or as a method for high-energy experiments in the region near to the circulating beam.

Organiser(s): John Miles (AT-MCS) and Werner Herr (AB-ABP)