The UA9 experiment on crystal-assisted collimation at the CERN-super proton synchrotron: tutorial 48

Channeling is the phenomenon constraining the path of a charged particle in a crystalline solid. High-energy charged particles can be captured in channeling states by the electromagnetic potential of the atomic planes in a crystal, thus performing quasi-harmonic oscillations between them. Particles channeled in a bent crystal are deflected by the bend angle. This provides a powerful method to steer particle beams. The UA9 Collaboration investigates how tiny bent crystals could assist and improve the collimation process in the Large Hadron Collider (LHC) at CERN in view of future ultra-high luminosity operation. The work is supported by CERN (European Organization for High-Energy Physics in Geneva Switzerland), the INFN (Istituto Nazionale di Fisica Nucleare in Italy), the Imperial College (in London), LAL (Laboratoire de l¿Accelereur Lineaire at Orsay, Paris), the PNPI (Petersburg Institute for Nuclear Physics, Gatchina, San Petersburg), the IHEP (Institute for High-Energy Physics in Protvino, Moscow) and the JINR (Joint Institute for Nuclear Research in Dubna, Moscow). This tutorial describes the main features of UA9 and the method used to measure the reduced flux of nuclear debris produced by channeled particles.