Speaker
Description
To reach a high accelerating gradient of 100 MV/m, the CLIC project under study at CERN uses a 23 cm long tapered normal-conducting travelling wave Accelerating Structure (AS) operating at 12 GHz. To preserve beam emittance at the 1 nm vertical-size collision point, 7 μm accuracy is required in the pre-alignment of the AS wrt the supporting girder. We have developed a dedicated test bench where a wire is used to materialize the electromagnetic axis in the AS and serves as a reference to fiducialise the structure in the accurate environment of a 3D Coordinate Measuring Machine (CMM). Our simulations have shown that a resolution of 1 μm is possible using a calibrated VNA. The recent experimental results and improvements will be presented and discussed.
