Accelerator Seminar: Alejandro Castilla Loeza

Accelerator Seminar: Alejandro Castilla Loeza

05/13/21 at 11:00 a.m.

Crab Cavities for High Luminosity LHC Upgrade at CERN: Preparing SRF Cavities for a test with protons In order to reach the desired levelled luminosity of >10³⁴cm^-2s^-1 in the High Luminosity Upgrade of the LHC (HL-LHC) at CERN, it is necessary to use crab cavities to correct the geometrical degradation due to the crossing angles at the principal interaction points (ATLAS and CMS). Prior to the integration in the LHC for the upgrade, foreseen for 2024, a test to prove feasible operation of such cavities with hadron beams, and to validate its novel cryomodule design, was flagged as crucial. A cryomodule with two cavities was built for testing with a proton beam in the SPS. Two bulk niobium double quarter wave cavities (DQW), for vertical crabbing, were fabricated, processed, and tested for validation at CERN. In this seminar, we present the different cavity preparation steps and summarize the results of the cryogenic tests performed in the vertical cryostat at the CERN-SM18 facility, for the DQW SPS prototype cavities, as well as some of the lessons learned.