Determination of interstrand contact resistance from loss and field measurements in LHC dipole prototypes and correlation with measurements on cable samples

Loss and field errors due to ramping in LHC accelerator dipole magnets are mainly determined by the contact resistance between the strands of the magnet cable. It is therefore important to develop cables having sufficiently high contact resistance in the magnets in order to ease operation of the future LHC collider during ramping. In this paper the contact resistance Rc and its distribution in the magnet windings are determined for several dipole prototypes using both the measured loss and field errors during ramping of the magnet. We compare these results with interstrand contact resistance measurements made on short samples of the cables used in these magnets.