Adjustable Permanent Quadrupoles Using Rotating Magnet Material Rods for the Next Linear Collider

摘要

This paper reports on two styles of permanent magnet adjustable quadrupoles for the next linear collider (NLC). Of the two types the wedge tuner is closest to meeting all the requirements for NLC. The strength of the gradient and higher harmonics are within specifications. Further work on balancing the strength of the tuning rods is required to meet the specification of a center shift of 1 micrometer. The effects of radiation exposure to the particular material used in the magnets needs to be understood. With the proper selection of material and shielding permanent magnet quadrupoles should be viable for the life of the NLC.