Simultaneous acceleration of H+ and H- in RFQ linacs

The beam dynamics calculations presented show that there is no fundamental reason why positive and negative beams cannot be accelerated simultaneously in an RFQ (radio frequency quadrupole) linac. These results reveal that the design criteria should be modified to give a larger longitudinal current limit for such an RFQ. The decision on whether to use one or two RFQs when accelerating positive and negative beams for injection into a drift tube linac would depend on several considerations: economics, the difficulty of matching two separate low-energy beams into the same RFQ, and the difficulty of matching the output beams into a magnetic focusing system.<>