Wake Field Acceleration A Way to TeV e+e--Collisions

Abstract

Future e + e -- accelerators in the energy range above 1 TeV will be linear colliders with a high accelerating gradient. For creating the high gradient, new concepts are investigated, such as wake field acceleration, which need driver beams with high current and short bunches. At DESY an experiment with a Wake Field Transformer has been set up, where electromagnetic wake fields of a highly charged hollow driver beam are spatially focussed, and the resulting high longitudinal electric field is used for the acceleration of a second beam. The basic idea, the layout of the experiment and the results are presented. In a stage-1 experiment several bunches, each of 50 to 100 nC charge, have been produced and accelerated to an energy of 6.5 MeV and bunched down to a length of 3–4 mm. Using longer bunches of 1 cm, a gradient of 8 MeV/m has already been measured in a short Wake Field Transformer section.