Performance Simulation of the LiCAS-RTRS Survey Train

The proposed LiCAS1 metrology system is a novel instrument dedicated to align and monitor the mechanical stability of a future linear high energy e+e− collider. LiCAS uses Laser Straightness Monitors (LSM) and Frequency Scanning Interferometry (FSI) [1, 2] for straightness and absolute distance measurements, respectively. This paper presents detailed simulations of a LiCAS system operating inside a Rapid Tunnel Reference Surveyor (RTRS train). With the proposed design it is feasible to achieve the required vertical accuracy of the order of O(200) μm over 600 m tunnel sections meeting the specification for the TESLA collider [3].