Toward an Improved High Strength, High RRR CMS Conductor

CMS (Compact Muon Solenoid) is a general-purpose detector designed to run at the CERN Large Hadron Collider (LHC), including a 4-layer superconducting solenoid with 6 m diameter by 12.5 m long free bore operated at 4 T and at 4.5 K. The Rutherford type superconductor, stabilized by high purity 99.998% aluminum, is reinforced by aluminum alloy sections welded to the superconductor by electron beam. Due to the high magnetic forces at nominal field inside the winding pack, the conductor itself represents a main structural component to get a self-supporting winding structure. In view of an upgrade oriented to a possible new project, an improvement of the mechanical performances of the reinforced conductor starting from the CMS concept has been considered, aimed to increase the reachable field based on an optimized layout