Inference of wakefield structure by driving longitudinal coupled bunch modes in Main Ring

Here, we present a qualitative study of coupled bunch effects for a partially filled Main Ring. Individual bunches interact with their environment via wake fields generated by the fundamental and higher parasitic structural modes. Bunches at the front of the train influence the motion of the following bunches. We employ a two-point correlation method to measure the phase oscillation between the reference bunch (bunch one) and a given bunch within the train, as a function of the bunch separations. The result of this analysis is a measure of the short range wakefield generated by the bunches.