Accelerator Science

Investigations of beam-beam effects in HL-LHC

Around the experimental regions of the Large Hadron Collider (LHC), beams travel in a common vacuum chamber and therefore experience the fields of the opposing beams - so-called ‘long-range interactions’. These are unavoidable and, being nonlinear, limit the LHC's luminosity. Studies of this effect are essential for designs crucial for the ongoing high-luminosity upgrade (or HL-LHC; a program to bring a factor-of-10 performance improvement to the LHC), due to begin operating in 2025. The usual method of investigating the effect is by multiparticle simulations, and TRIUMF is part of the international collaboration charged with these calculations. These are compute-power limited, so it is highly desirable that an alternative analytic model be found. Recently, we have discovered such a model. This has the potential of making beam-beam calculations more tractable.