Saturation Induced Field Errors in the LHC Main Dipoles

The program package ROXIE has been developed at CERN for the design and optimization of the coil geometries for the superconducting magnets for the Large-Hadron-Collider, LHC. It has been extended to the calculation of iron induced effects applying a reduced vector potential formulation. The method allows accurate computation of the multipole errors in the magnets and allows the distinction between the effects resulting from the coil geometry and the yoke geometry. The aim of this report is to describe the computational method as well as to give the newest estimates on the multipole errors to be expected in the LHC main dipoles.