Ultrarelativistic nuclei in a crystal channel: Coulomb scattering, coherence, and absorption

Abstract

We incorporate the effect of lattice thermal vibrations into the Glauber-theory description of particle and nucleus-crystal Coulomb interactions at high energy. We show that taking the lattice thermal vibrations into account produces a strong absorption effect: the phase shift function of the multiple-diffraction scattering on a chain of N identical atoms acquires a large imaginary part, and the radius of the absorption region in the impact parameter plane grows logarithmically with N. Consequences of this observation for the elastic and quasi-elastic Coulomb scattering are discussed. The practically interesting example of the coherent Coulomb excitation of ultrarelativistic particles and nuclei passing through a crystal is considered in detail.