First Results of Beam Dynamics Simulation in electron injector linac for FCC-ee

New high-energy frontier project FCC is now under development at CERN. It is planed that all three modes as ee, hh and eh will be available for FCC. New injection system for FCC-ee is planned to consist of new ~ 2 GeV electron linac and electron-positron converter. Two possible layouts for further beam acceleration are discussed. The high-energy 14 GeV linac is the first layout and the booster synchrotron is the second one. Pre-injector linac design will have two regimes: ~250 pC bunches for injection and ~6 nC bunches for e⁻/e⁺ conversion. In the second case we will have extreme parameters: bunch charge up to 6 nC in 10 ps, up to 10 bunches per pulse and the pulse repetition rate up to 100 Hz. Such beam parameters lead to significant design difficulties caused by very high influence of Coulomb field in the near-cathode region and high peak beam loading. First results of beam dynamics simulation in FCC-ee injection linac and near-cathode dynamics problems are discussed in the report.