Along many low energy beam transport (LEBT) systems transverse hadron beam matching to a subsequent radio frequency quadrupole (RFQ) is performed by magnetic quadrupole multiplets. Large apertures combined with short distances between the quadrupoles lead to overlap of individual singlet fields and significantly impact on the effective beam optics. Systematic measurements of beam transmission through an RFQ have been done and compared to beam dynamics simulations. For the latter, simplified hard-edge quadrupole fields were replaced by measured field data. It turned out that the hard-edge model is not sufficiently accurate to achieve acceptable agreement between calculated and measured beam properties.

沿着许多低能束传输（LEBT）系统，横向强子束与随后的射频四极（RFQ）的匹配是由磁性四极多重峰完成的。大孔径加上四极子之间的短距离导致各个单线态场重叠，并严重影响有效的光束光学系统。已经完成了对通过RFQ进行的光束传输的系统测量，并将其与光束动力学仿真进行了比较。对于后者，简化的硬边四极场被测得的场数据取代。事实证明，硬边缘模型不够精确，无法在计算和测量的射束特性之间达成可接受的一致性。