STUDY OF OFFSET COLLISIONS AND BEAM ADJUSTMENT IN THE LHC USING A STRONG-STRONG SIMULATION MODEL HORIZONTAL OFFSET (µM)

The bunches of the two opposing beams in the LHC do not always collide head-on. The beam-beam effects cause a small, unavoidable separation under nominal operational conditions. During the beam adjustment and when the beams are brought into collision the beams are separated by a significant fraction of the beam size. A result of small beam separation can be the excitation of coherent dipole oscillations or an emittance increase. These two effects are studied using a strong-strong multi particle simulation model. The aim is to identify possible limitations and to find procedures which minimise possible detrimental effects.