The ballistic alignment method

In order to preserve the very small beam emittance in the main linacs of future high-energy linear colliders a new alignment method, the so-called ballistic alignment method, has been developed. A description of the method is given and it is applied to the Compact Linear Collider (CLIC) [1]. In this scheme the quadrupoles are divided into bins which are corrected one after the other. In the first step, the quadrupoles in a bin are switched off to use a ballistic beam to align the beam position monitors (BPMs). Next, a simple one-to-one correction is used to align the quadrupoles. The dependence of the emittance growth on different error sources is investigated.