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Synchrotron high-energy X-rays were used in an attempt to estimate nanoprecipitate size and size distribution in Nb3Sn powder-in-tube wires with ZrO2 or HfO2 artificial pinning centers via small angle X-ray scattering (SAXS). The effect of sample preparation was studied but measurements for as-received and for partially etched wires were not successful. Extracted sub-elements appeared to show more scattering contrast due to the lower number of phases, but no particle size could be extracted in this first attempt. Analysis of TEM data from the literature showed large particle size distribution (PSD) for different heat treatment conditions, suggesting that PSD could likely never be measured with SAXS due to a smeared signal. Experimental challenges with in-situ measurements revealed the sensitivity of infra-red furnaces and to changes in sample emissivity. The use of in-situ wide angle X-ray scattering data was successful in estimating the wire temperatures from the lattice parameter of copper and could be used in future heat treatment studies to better understand tin oxide dissolution.

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 of the 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 article, we present a summary of: 1) the fabrication and test data for 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.