Radiofrequency Quadrupole Accelerators for the RIA Facility
Andrei Kolomiets, IETP, Moscow
The Rare Isotope Accelerator (RIA) Facility will consist of several
Radio-Frequency Quadrupole (RFQ) sections since RFQs are most efficient
for acceleration of low-velocity ions. The primary design goal for the
Driver RFQ is to establish a low output emittance so that the acceleration
of multiple-charge-state beams through the rest of the linac becomes straightforward.
Low longitudinal emittance is achieved by using an external multi-harmonic
buncher and an RFQ of modified design. Three RFQ sections operating at
very low frequencies 12 MHz and 24 MHz were designed for the acceleration
of radioactive ions including singly charged ions with mass number up to
240. To increase acceleration efficiency a special accelerating structure,
so-called Hybrid RFQ, was proposed and designed.