Dynamic aperture models for a time-varying high luminosity LHC lattice

The evaluation of dynamic aperture (DA) under time-dependent variations of lattice parameters is essential for understanding the long-term stability of particle motion in the Large Hadron Collider (LHC) and enhancing the future performance of the High-Luminosity LHC (HL-LHC). In this work, we develop DA models that address the complexities introduced by time-varying effects, with a focus on the operational challenges posed by luminosity levelling. Building on established DA scaling laws, we aim at capturing the impact of evolving machine conditions during levelling. An initial simulation study is presented that compares the effects on DA of different levelling schemes that are expected to be routinely used during the HL-LHC operation, providing key insight into extending current DA models to accommodate time-dependent perturbations.