Injector linac for Super-ALIS

An injector linac is described for Super-ALIS, the dedicated superconducting storage ring for X-ray lithography at NTT LSI Laboratories. Super-ALIS uses a low-energy injection scheme which requires the injection efficiency to be raised, since stacking is unavailable due to the low injection energy levels. Improving the efficiency of the injector required a large current, low transverse emittance, and a narrow energy spread; a low-emittance electron gun, double prebunchers, standing-wave accelerator cavities, and an energy compression system were used in the injector to fulfil these strict requirements. The characteristics of the system are summarized; acceleration frequency is 2856.65 HMz; beam energy and current are 15 MeV and 270 mA, respectively; beam energy spread is 1% (FW); beam pulse width is 2 mu s; and the maximum repetition rate is 3 Hz.<>