Vol. 2 (2018): Proceedings of "Tracking Collimation" ICFA Workshop
Beam collimation and machine protection have become essential aspects for modern high stored energy accelerators. The understanding of operating facilities and the performance extrapolations for future machines demands unprecedented accuracy in simulations of beam cleaning systems. This is critical for the Large Hadron Collider (LHC) and for its High-Luminosity (HL) upgrade project and for the Future Circular Collider (FCC) presently under study, but also for a number of other lower energy accelerators that operate with high hadron beam intensities. These simulations require precise tracking of halo particles with large betatron amplitudes and off-momentum errors as well as precise modelling for the scattering with collimator materials and aperture checks. Several tools have been developed by different teams, putting together the required competence to improve simulation accuracy on all fronts. High-efficient cleaning simulations require in addition very demanding CPU power, as high statistics is required for loss predictions at the 1e-5 level and below. In recent years, important progress was made in the context of FP7 programmes on LHC collimation studies.