The last short model of the Nb3Sn quadrupole was limited below nominal current by one coil: to overcome this issue, the limiting coil shall be replaced magnet and the magnet shall be tested in summer. The results of the test on US prototype has been reported here.
The first prototype of the nested corrector MCBXFB has been manufactured and tested in early 2019. The magnet, made of an horizontal and of a vertical dipole, reached the required performance in each plane. However, when powering both field directions, a limitation appears, possibly related to the torque in the coils ends. An iteration on the parameters of the mechanical assembly is being done to overcome this issue.
For the high order correctors, all prototypes have been completed and reached performance. One iteration has been necessary for the last of the five magnets, i.e. the skew quadrupole corrector, which had one coil developing a short during the test. After a coil replacement, and a consolidation of the design of the coil, also this magnet reachedtarget performance in June 2019. The contract for the series has been tendered and production will start soon in SAES-RIAL Vacuum. A dodecapole and a skew quadrupole are the first magnets ready for the IT STRING.
A third model of the separation dipole D1 is being assembled, to check performance reproducibility. A test is foreseen in the second half of 2019. The tender for prototype and series has been attributed in May to Hitachi.
The short model of the recombination dipoles has been tested in early 2019, reaching target performance in one aperture. The second aperture had a non-conformity in the assembly, and is being repaired. The tender for the prototype and series has been assigned in first half of 2019 to ASG superconductors.
The prototype of the D2 corrector, based on canted cos theta design, has been successfully tested in first half of 2019. China agreed to provide these magnets as in kind contribution, and the construction of the first Chinese prototype is ongoing in X’ian (WST).
