Crystal channeling of LHC forward protons with preserved distribution in phase space

We show that crystal can trap a broad (x,x′,y,y′,E) distribution of particles and channel it preserved with a high precision. This sampled-and-hold distribution can be steered by a bent crystal for analysis downstream. In simulations for the 7 TeV large hadron collider, a crystal adapted to the accelerator lattice traps 90% of diffractively scattered protons emerging from the interaction point with a divergence 100 times the critical angle. We set the criterion for crystal adaptation improving efficiency ∼100-fold. Proton angles are preserved in crystal transmission with accuracy down to 0.1 μrad. This makes feasible a crystal application for measuring very forward protons at the LHC.