Development of superconducting tuning quadrupole corrector (MQT) prototypes for the LHC

Abstract

Abstract-The main quadrupoles of the Large Hadron Collider (LHC) are connected in families of focusing and defocusing magnets. In order to make tuning corrections in the machine a number of quadrupole corrector magnets (designated MQT) are necessary. These 56 mm diameter aperture magnets have to be compact, with a maximum length of 395 mm and a coil radial thickness of 5 to 7.5 mm, while generating a minimum field gradient of 110 T/m. Two design options have been explored, both using the "counter-winding" system developed at CERN for the fabrication of low cost corrector coils. The first design, with the poles composed of two double-pancake coils, each counter-wound using a single wire, superposed to create 4-layer coils, was developed and built by ACCEL Instruments GmbH. A second design where single coils were counter-wound using a 3-wire ribbon to obtain 6-layer coils was developed at CERN. This paper describes the two designs and reports on the performance of the prototypes during testing.

Principles developed for the construction of the high performance, low-cost superconducting LHC corrector magnets

“…Both solutions worked well [5]. The second solution, using the flat cable, has been adopted for the fabrication of the final magnets (Fig.…”

Inner triplet corrector package MQSXA for the LHC

“…The design of the skew quadrupole part being very similar to the MQT tuning quadrupole modules [2] it was decided to limit the prototype to the part consisting of the three nested windings. The cross-section of these nested windings is shown in Fig.…”