  By the end of October 2022, the US HL-LHC Accelerator Upgrade Project (AUP)
had completed fabrication of ten MQXFA magnets and tested eight of them. The
MQXFA magnets are the low beta quadrupole magnets to be used in the Q1 and Q3
Inner Triplet elements of the High Luminosity LHC. This AUP effort is shared by
BNL, Fermilab, and LBNL, with strand verification tests at NHMFL. An important
step of the AUP QA plan is the testing of MQXFA magnets in a vertical cryostat
at BNL. The acceptance criteria that could be tested at BNL were all met by the
first four production magnets (MQXFA03-MQXFA06). Subsequently, two magnets
(MQXFA07 and MQXFA08) did not meet some criteria and were disassembled. Lessons
learned during the disassembly of MQXFA07 caused a revision to the assembly
specifications that were used for MQXFA10 and subsequent magnets. In this
paper, we present a summary of: 1) the fabrication and test data of all the
MQXFA magnets; 2) the analysis of MQXFA07/A08 test results with
characterization of the limiting mechanism; 3) the outcome of the
investigation, including the lessons learned during MQXFA07 disassembly; and 4)
the finite element analysis correlating observations with test performance.
