Quench performance of Fermilab model magnets for the LHC inner triplet quadrupoles
As part of the US LHC program to develop high gradient superconducting quadrupoles for the LHC interaction regions, a series of 2 meter long model magnets has been built and tested at Fermilab. This R&D program was used to refine the mechanical and magnetic design, optimize fabrication and assembly tooling and ensure adequate quench performance. The final design, fabrication, and assembly procedures developed in this program have produced magnets which meet the LHC requirements of operating at 215 T/m with excellent magnetic field harmonics. This paper summarizes the test results of the last five model magnets, including quench tests over several thermal cycles, and excitation current ramp rate and temperature dependence studies.