Development of MQYY: A 90-mm NbTi Double Aperture Quadrupole Magnet for HL-LHC

In the context of the HL-LHC project, a NbTi double aperture quadrupole magnet called MQYY is being developed. This 90-mm-aperture quadrupole magnet has a magnetic length of 3.67 m and an operating gradient of 120 T/m at 1.9 K. Its development is done along two parallel paths: 1) the design, fabrication, and test of a short model; 2) the design and fabrication of two full-scale prototypes in industry within the H2020 EU Pre-Commercial Procurement project QUACO implemented by CERN, CEA, CIEMAT, and NCBJ. We report here on the short-model design choices the status of its fabrication and the preparation of the tests. In particular, we describe the magnetic and mechanical design relying on self-supporting collars, the protection aspects, the fabrication, and the cold test preparation. Finally, we present the unusual scheme of the QUACO project leading to the prototypes fabrication.