Pre-Alignment of CLIC - Rasclic versus WPS
Summary
Two alignment systems for CLIC were studied, the Rasnik system family (Rasnik and Rasdif) and the Wire Positioning System (WPS). Rasnik, Rasdif and WPS were compared to each other over a length of 4.02 m. The systems agreed with each other with an accuracy of 20μm in an unstable environment and with an accuracy of 10 μm in a stable environment.
Rasdif was compared to WPS over a length of 140 m. This was done for when Rasdif was in air and for when Rasdif was in vacuum. Both systems were in agreement with each other with an accuracy of 15 μm. The instability of the light source of the Rasdif system that was used turned out to be the largest cause for variations in the data.