Intra-beam Scattering and Luminosity Evolution for HL-LHC Proton Beams

Intra-beam scattering (IBS) in the LHC proton beams will be stronger in the future HL-LHC than at present because of the higher beam intensities, small emittances and new optics. The intensity decay will be due to both IBS and “burn-off” by the luminosity. We calculate IBS emittance growth rates with MADX and the Collider Time Evolution (CTE) program for two ATS optics versions, ATS-V6.503 and SLHCV3.1b, and different settings of the crossing angle and required corrections. The calculations are done for injection (450GeV) and collision (7TeV) energy for various beam conditions. Moreover, CTE simulations of the emittance, bunch length, intensity and luminosity evolution during a fill are presented.