Design of a control system for stepper motors with micro-metric precision employed in the beam emittance measurement of the Linac4 at CERN

A new linear accelerator (Linac4) is being designed to replace its predecessor (Linac2) at CERN. The new Linac4 will double the initial intensity giving an injection energy of up to 160 MeV. It will be an essential component of the LHC (Large Hadron Collider). To assess the quality of the beam, monitoring systems are placed along the beam pipe, being one of them devoted to measure its emittance, the so-called emittance scanner. The measurement of the emittance is important since it constitutes one of the two main parameters that limits the overall LHC performance, being the other parameter the energy of the beam. While the energy level of the beam can be modified during different phases at CERN, the beam emittance cannot; it is determined by the first source that produces the beam. The beam emittance directly influences the amount of particles colliding. For this purpose, the Linac4 emittance scanner will be placed on the very first step of the whole CERN accelerator complex right after the particles source. This project consists in the development of a control system for the emittance scanner of the Linac4 using LabVIEW as programming environment. This task was assigned to the author as part of his student placement at CERN, which has been achieved during a 5 months period. It has to be said that the whole project is in a continuous process of update. The main contribution of the author to the emittance scanner of the Linac4 has been the creation of a control system that allows the user to execute a scan of the beam by introducing a set of scanning parameters, and displays back on the user interface the acquired measurements. Part of the public information of this project has been assembled to give form to this student final degree project.