Beam-beam interactions with COMBI

During the summer of 2015 I spent eight weeks at CERN for the Summer Student Programme. This report summarizes the project on beam-beam interactions with a crossing angle that took place at the Beams Department. Beam-beam interactions with a crossing angle were studied from the simulation framework COMBI (COherent Multibunch Beam-beam Interaction). These studies were largely performed by analyzing the tune Fourier spectra to assess the tune shifts. Hints of new insights have been obtained on the crossing angle behaviour of the Yokoya factor, which relates the tune shift to the beam-beam parameter. Furthermore, the implementation of a crossing angle into the COMBI code is outlined, as well as the insertion of the longitudinal part of the beam-beam eects to model a 6D interaction.