As part of the U.S. contribution to the HL-LHC Accelerator Upgrade Project (AUP), Fermilab is designing and building cold masses suitable for use in the LHC interaction regions. The cold mass provides a vacuum-tight helium enclosure for the magnets. Two magnets are aligned both axially and in cross section at Fermilab based on survey and warm magnetic measurements. Bus work and instrumentation is added. A welded stainless steel vacuum-tight shell surrounds the two magnets, and the structure is prepared for insertion into the cryostat. This paper summarizes the design of the cold mass including alignment, bus work, weld details, and instrumentation.

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Collaborators on the design of a Tevatron Superconducting Linear Accelerator (TESLA) are working toward construction of a test cell consisting of four full length cryostats, 12 meters long, each containing eight, 9-cell superconducting RF cavities. In order to ensure that each cavity meets its performance requirements, 'as received' structures will be tested in a vertical dewar prior to installation in the cryostat vessels.In addition, the dewar system will accommodate cavities installed in their helium containment vessels for testing if performance problems occur during later stages of fabrication. The vertical dewar system permits testing of the RF performance and high power processing of the cavity structures at their operating temperature of 1.8 K. The design of the cryogenic system, vacuum system, RF input, test instrumentation, and tuning system will be described in detail.

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The muon-to-electron conversion (Mu2e) experiment at Fermilab will be used to search for the charged lepton flavor-violating conversion of muons to electrons in the field of an atomic nucleus. The Mu2e experiment is currently in the construction stage. The scope of this paper is the cryogenic distribution system and superconducting power leads for four superconducting solenoid magnets: Production Solenoid (PS), an Upstream and Downstream Transport Solenoids (TSu and TSd) and Detector Solenoid (DS). The design of the cryogenic distribution system and the fabrication of several sub-systems was reported previously. This paper reports on additional fabrication and installation progress that has been performed over the past two years. Lessons learned during fabrication and testing of the cryogenic distribution system components are described. In particular, the challenges and solutions implemented for aluminum welding are reported. A description of the process used to qualify the welding procedure and welders for welding the aluminium stabilized NbTi superconducting power leads is provided. Additionally, the progress made with regards to installing the power leads into the cryogenic Feedboxes is covered.