Multi-GeV energy gain in a plasma-wakefield accelerator

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 1.8x10(10) electrons is compressed to 20 mu m longitudinally and focused to a transverse spot size of 10 mu m at the entrance of a 10 cm long column of lithium vapor with density 2.8x10(17) atoms/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.