Specifications of the Field Quality at Injection Energy of the New Magnets for the HL-LHC Upgrade Project

The HL-LHC project relies on new magnet designs and technologies to achieve very small beta* values. In particular, Nb$_{3}$Sn magnets show large allowed multipole imperfections at low current. These field imperfections may have a non-negligible impact on the dynamic aperture and beam life time in the HL-LHC, also because of the smaller-than- nominal beta* values foreseen IR1 and IR5 at injection energy, which aims at decreasing the dynamic range of the squeeze and therefore contributing to optimize the turn around time. The paper describes an analysis of the machine performance based on analytical estimates and tracking simulations with the goal of providing field quality specifications for the new magnets.