Crystal bending of the LHC beam for in situ calibration of ATLAS and CMS calorimeters

The physical possibility for bending the LHC protons and ions by a huge angle from 1° to 20° in the energy range of 0.45–7 TeV by means of a bent single crystal of silicon or germanium is studied. Such an application can be useful, e.g. for calibration of CMS or ATLAS calorimeters in situ by the LHC beam of precisely known energy. We show by simulations that this application would be feasible at the LHC, and report the experience of IHEP Protvino in bending 70 GeV protons by 9° (150 mrad) during 10 years of experiments in 1994–2004.