The beam mismatches in the RFQ dynamics design

The dynamics design of radio frequency quadruple (RFQ) Linacs for high intensity beams had been extensively studied by LANL and generalized method had been proposed, however, the beam mismatches are still not paid enough attentions in this dynamics design method. As the beam envelope mismatch is the major source of formation of halo and related emittance growth in high intensity linac, so some extensions based on the generalized method are developed, where the causes of beam mismatch in RFQ are analyzed and a new dynamics method is proposed to minimize the emittance growth and the related beam loss. A dynamics example is given to prove this design method.