Test results of the prototype combined sextupole-dipole corrector magnet for LHC

The corrector magnet for the Large Hadron Collider (LHC) contains a 1.5-T dipole for orbit correction and a 8000 T/m/sup 2/ sextupole for chromaticity correction. The dipole has for compactness been mounted around the sextupole coil. A full-scale prototype of 1.3-m length has been fabricated and tested. The coils were first tested at 4.2 K. It appeared that the training of the impregnated coils could be strongly reduced by increasing the radial precompression. The coils were subsequently cooled to the operational temperature between 1.8 and 2 K and the field quality was measured with a harmonic rotating coil. The results of the tests show that the combined dipole-sextupole corrector magnet does meet the desired field strengths.>