Design of single harmonic buncher for VEC

ECR ion source provides dc beam. When dc beam is injected into the cyclotro n, only a part of it is accepted in the desired phase range for the proper acceleration. In order to enhance the beam current from VEC, which uses all external injection system, a single harmonic buncher for bunching heavy io n beam from the ECR ion source has been designed indigenously. Recent exper iments with VEC beam showed a significant enhancement in extracted beam cur rent and the time structure of extracted beam pulse. Discussion about theor y of bunching, design and the results are presented.