Accelerator Upgrade Program (AUP) cavity status and preparations at JLab 

Work is progressing well for the crab cavity portion of the US contribution to the HL-LHC Project.

All contracts are in place with the industrial supplier for the manufacturing of the RF-dipole (RFD) crab cavities, where activities have now reached peak production after years of development.

The first two bare RFD cavities have been completed successfully and are currently undergoing cold tests in the US at Jefferson Lab (JLab) and Fermilab. Once qualified, these will be shipped back to the supplier for jacketing; magnetic shields and helium tank materials needed for the jacketing steps are already in hand (see figure 1), and the jacketing process is already validated thanks to the recent completion of a jacketed prototype (see figure 2). 

Cavities will be tested again at JLab with in-house-built HOM dampers installed, prior to final shipment to TRIUMF where the cryomodules will be assembled.

Preparations for cryostating at TRIUMF 

Components for TCM0 - outer vacuum chamber (OVC), thermal screen, multi-layer insulation (MLI), bi-phase and cryo-lines - are in production, and several series orders - OVC, mu-metal, MLI, bi-phase and cryo-lines - have been awarded. Infrastructure upgrades are in progress, and the final design of a new clean room is complete, with a building permit issued. Installation will commence in August 2024.

A first article fully dressed prototype cavity is expected to arrive at TRIUMF from the AUP in early December 2024. The cavity will be requalified at TRIUMF before being accepted for assembly. The TCM0 string will be assembled with the prototype cavity plus a dummy cavity (now received). In preparation for the first cavity, TRIUMF will cryo-cool the dummy cavity to qualify 2K cooldown. Assembly tooling fixtures for the IT String assembly are mostly received with the complement expected by the end of June. Plans have been initiated to prepare a cryomodule qualification centre at TRIUMF.