Local beating corrections with orbit bumps in the LHC

The purpose of this Master thesis is to explore further possibilities to increase the Luminosity of the Large Hadron Collider (LHC) by improving the optics correction. As a basic principle, turn-by-turn data is measured with BPMs (beam position monitors) and the local phase of the betatron oscillation is obtained by a harmonic analysis. The beta function describes the envelope of the beam motion if multiplied by the emittance and can be extracted from the turn-by-turn data by utilising the N-BPM method after a spectral analysis. If there are lattice imperfections, then they will perturb the beam motion and the distortion oscillates around the ring. This phenomenon is generally called beating. In order to increase the Luminosity, the beta function at the interaction point (IP) has to be reduced to a minimum (Hourglass effect limits the Luminosity if the longitudinal beam size becomes comparable in magnitude to the beta function at the IP). This is realised by the achromatic telescopic squeezing scheme (ATS-optics) for the High Luminosity Large Hadron Collider (HL-LHC). The disadvantage of a small beta function at the IP is a very large beta function in the triplets. Hence, any error of the magnets in the triplet causes a significant beating of the optics functions and perturbs the beta function at the IP as well. Fortunately, the triplets are powered individually, wherefore the field strengths can be adjusted separately. After applying corrections based on measurements, the distortions within the lattice are equalized as much as possible by varying the knobs. The special optics configuration of the ATS sequence also enlarges the beta function in the arcs, where the quadrupoles are powered in series. A possible correction strategy for the arcs is to use feed-downs from sextupoles by applying orbit bumps to the beam. The feasibility of this approach has been demonstrated. This Master thesis focuses on the validation of the correction method and investigates potentially degenerated orbit bumps. In addition, the measurement principle for the lattice functions is tested at the ELENA synchrotron.