Weak-strong beam-beam simulations for the Large Hadron Collider

Abstract

A weak-strong simulation code is used to study the single-particle stability in the presence of triplet field errors, head-on collisions, and long-range beam-beam interactions at the Large Hadron Collider. We present the dependence of the simulated transverse diffusion rate on various parameters, such as starting amplitude, working point in tune diagram, crossing angle, beta function at the interaction points (IPs), beam current, triplet nonlinearities, tune modulation, and a transverse offset at one of two IPs. For several examples, we perform a frequency map analysis à la Laskar, to obtain tune footprints and the tune variation in time. A cursory look at the effect of a Möbius lattice is also reported.