Electron beam spectrum (IMAGE) Imperial College London Caption Electrons are ejected from the plasma accelerator at almost the speed of light, before being passed through a magnetic field which separates the particles by their energy. They are then fired at a fluorescent screen, shown here Credit Rob Shalloo Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.