A single-shot method to reconstruct the transverse self-wakefields acting on
a beam, based only on screen images, is introduced. By employing numerical
optimization with certain approximations, a relatively high-dimensional
parameter space is efficiently explored to determine the multipole components
of the transverse-wakefield topology up to desired order. The reconstruction
technique complements simulations, which are able to directly describe the
wakefield composition based on experimental conditions. The technique is
applied to representative simulation results as a benchmark, and also to
experimental data on wakefield observations driven in dielectric-lined
structures.Comment: 10 pages, 8 figure
