Magnetic Field Design of a Full-Scale Prototype of the HL-LHC Beam Separation Dipole With Geometrical and Iron-Saturation Corrections

High Energy Research Organization (KEK) has developed three short-scale model magnets of the beam separation dipole, MBXF, which is to be installed for the High Luminosity Large Hadron Collider, HL-LHC, in CERN. We will soon undertake production of a prototype of MBXF and its magnetic design has to be finalized before the fabrication. We established a strategy for designing the new coil cross section by taking into account different error sources for its field quality. In this paper, focused on b
₃
, we describe how the final b
₃
integral, which should be within 2.9 units according to the acceptance criteria, is achievable.