Title: Multi-proton bunch driven hollow plasma wakefield acceleration in the nonlinear regime,
Abstract: Proton-driven plasma wakefield acceleration has been demonstrated in
simulations to be capable of accelerating particles to the energy frontier in a
single stage, but its potential is hindered by the fact that currently
available proton bunches are orders of magnitude longer than the plasma
wavelength. Fortunately, proton micro-bunching allows driving plasma waves
resonantly. In this paper, we propose using a hollow plasma channel for
multiple proton bunch driven plasma wakefield acceleration and demonstrate that
it enables the operation in the nonlinear regime and resonant excitation of
strong plasma waves. This new regime also involves beneficial features of
hollow channels for the accelerated beam (such as emittance preservation and
uniform accelerating field) and long buckets of stable deceleration for the
drive beam. The regime is attained at a proper ratio among plasma skin depth,
driver radius, hollow channel radius, and micro-bunch period.