Simulations and measurements of collisional losses with Pb beams at the LHC

Abstract

Abstract For about one month per operational year, the Large Hadron Collider (LHC) at CERN works as a heavy-ion collider. Four one-month Pb-Pb runs have been executed so far as well as two p-Pb runs. The LHC heavy-ion programme is scheduled to continue in the future, featuring increased luminosity and beam energy. Beam losses caused by ions fragmenting in the collision process risk introducing performance limitations. Losses occur immediately downstream of the collision points as well as at other locations in the ring, through multi-turn beam dynamics processes and interactions with ring collimators. This paper presents first simulations of collisional loss patterns for nuclear beams using a new simulation approach that relies on the SixTrack-FLUKA coupling simulation tool, including nuclear fragmentation and electron capture in the collisions. Simulations of the 2018 Pb-Pb and 2016 p-Pb runs are compared against experimental data and the prediction of collisional losses for future Pb-Pb and p-Pb runs is shown.