Beam Dynamics Analysis Of Heavy Ion Injection Into The Kek Digital Accelerator

An electrostatic kicker is used for heavy ion beam injection into the KEK digital accelerator (DA) ring. A voltage of 20 kV, which must be immediately turned off after injection, is applied across the electrostatic electrodes before injection so as to deflect the injected beam into the ring orbit. An SI-Thyristor Matrix Array (SI-Thy MA) has been developed to replace the conventional thyratron switching device. Long ringing in the turn-off voltage affects the longitudinal motion of the injected beam bunch, resulting in the formation of microstructure. The physics behind the microstructure formation is discussed in detail. (C) 2016 The Japan Society of Plasma Science and Nuclear Fusion Research