Synihesis of MBE-4 Accelerating Waveforms

High-current beam transport with multiple beam arrays

“…5. These waveforms were approximately synthesized in a numerical study [13] by adding elementary waveforms which were similar to those obtained in laboratory tests [35] [36]. They are curves of positive and negative initial curvatures and an almost flat-top curve with finite rise and fall times.…”

“…[ 10]* An ion induction linac called the Multiple Beam Experiment (MBE-4) is being constructed at LBL [ 11] to test multiple beam transport arrays [ 12], and demonstrate acceleration and bunch length compression of space charge dominated ion beams [13]. Construction is scheduled to be completed late in 1986.…”

Developments in Accelerators for Heavy Ion Fusion

“…Voltage waveforms that must be supplied at the discrete accelerating gaps to accomplish a desired schedule for current amplification has been developed in the past year by Kim and others [25]. To accomplish current amplification, the natural distension of bunch length such as occurs, for example, in an rf linac (a constant current accelerator), must be halted by applying a higher accelerating field to the tail of the bunch than to the head.…”

MBE-4, a Heavy Ion Multiple-Beam Experiment

“…It basically consists of an injector system to generate and condition four Cesium ion beams, accelerator sections incorporating 24 accelerating gaps in 30 focussing lattice periods, plus associated diagnostic, vacuum and control devices. MBE-4 and its experimental program are described further in other papers at this Conference [3][4][5][6][7][8] and in a separate report [9].…”

“…Two or more pulsers at each gap will provide special waveforms with up to 30 kV acceleration [8]. The applied vo ltages must not only accelerate the ion beams but must also accelerate the tail more than the head of the beam bunch in order to achieve current amplification.…”