Tsing Hua Univ, Dept Engn Phys, Beijing 100084, Peoples R China
; Chinese Acad Sci, Inst High Energy Phys, Beijing 100039, Peoples R China
A method based on the transverse particle motion equation is described for the calculation of beam acceptance for RFQ accelerators. The result is given for a four-vane type RFQ accelerator with specific structure parameters. The system acceptance for proton beam is 0.0153 cut . rad in x-x' phase space, and 0.0114 cm . rad in gamma-gamma' phase space. The method can also be applied for the calculation of acceptance for other RF accelerators with known structures and linear transverse electric fields.