Multi-GeV Energy Gain in a Plasma-Wakefield Accelerator

Abstract

A plasma-wakefield accelerator has accelerated particles by over 2.7 GeV in a 10 cm long plasma module. A 28.5 GeV electron beam with $1.8\ifmmode\times\else\texttimes\fi{}{10}^{10}$ electrons is compressed to $20\text{ }\text{ }\ensuremath{\mu}\mathrm{m}$ longitudinally and focused to a transverse spot size of $10\text{ }\text{ }\ensuremath{\mu}\mathrm{m}$ at the entrance of a 10 cm long column of lithium vapor with density $2.8\ifmmode\times\else\texttimes\fi{}{10}^{17}\text{ }\text{ }\mathrm{\text{atoms}}/{\mathrm{cm}}^{3}$. The electron bunch fully ionizes the lithium vapor to create a plasma and then expels the plasma electrons. These electrons return one-half plasma period later driving a large amplitude plasma wake that in turn accelerates particles in the back of the bunch by more than 2.7 GeV.