The three-harmonics double-drift buncher at the Munich heavy ion postaccelerator

A three-harmonics double-drift buncher has been developed and constructed to increase the intensity of the heavy ion beams from the postaccelerator at the Munich MP tandem. This buncher consists of three lambda/4 coaxial line resonators which are operated at the frequencies f, 2f and 3f (f resonance frequency of the postaccelerator). The buncher resonators are positioned at the high energy side of the tandem, the resonators f and 2f about 20 m, the 3f-resonator 17.5 m before the postaccelerator. The intensity of the target currents is increased by a factor 2-3 with the help of this harmonic buncher compared to the currents obtained with the old buncher, consisting of one single lambda/4 resonator. (orig.)