High-efficiency deflection of high-energy protons through axial channeling in a bent crystal

Phys Rev Lett. 2008 Oct 17;101(16):164801. doi: 10.1103/PhysRevLett.101.164801. Epub 2008 Oct 16.

Abstract

Beam deflection due to axial channeling in a silicon crystal bent along the 111 axis was observed with 400 GeV/c protons at the CERN Super Proton Synchrotron. The condition for doughnut scattering of protons by the atomic strings of the crystal was attained. Such a condition allowed one to observe a beam deflection of 50 murad with about 30% efficiency. The contribution of hyperchanneled states of protons to the observed beam deflection was less than 2% according to simulation results.