Magnetic Field Measurements of First Pre-series Full-Length 4.2 m Quadrupole MQXFA03 Using PCB Rotating Coils for the Hi-Lumi LHC Project

The U.S. Hi-Lumi LHC Accelerator Upgrade Project (AUP) and CERN have joined efforts to develop high field quadrupoles for the upgrade. US national laboratories in AUP project will deliver 10 magnets each cryostat has two 4.2 m gradient it. These are made of Nb3Sn conductors, with large aperture (150 mm) integrated 556.9 T. This paper reports on magnetic measurements performed during vertical test at Brookhaven National Laboratory (BNL) 2019-2020. A warm measurement Z-Scan (+/-15 A) 42 Z-positions before cool-down was BNL. results were directly compared data measured LBNL magnet assembly. Measured harmonics center offsets (ΔX ΔY) provided timely informative diagnostics structure's shape both cold temperatures. new centering fixture designed added better bore tube which contains rotating coil probe. After quench training 16.47 kA achieved, a complete set (Z-Scan I-Scan from 960 back made. Periodic axial variation allowed nonallowed observed is related radial and/or mid-plane variations along axis. Overall, average straight section within required boundaries.