The Development of the Superconducting Dipoles D2 for the High Luminosity Upgrade of LHC

The recombination dipoles D2 (MBRD) for the luminosity upgrade of the Large Hadron Collider (LHC) are double aperture magnets to be placed on each side of ATLAS and CMS experiments, generating 4.5 T along a magnetic length of 7.78 m and a bore diameter of 105 mm. Its development plan foresees the construction of a short model 1.6 m long, followed by a prototype and by the series of 6 magnets. The magnet design was carried out at INFN Genova in a collaboration framework with CERN and the construction is ongoing in the industry (ASG Superconductors, Italy). The short model activities have just been accomplished after a successful power test performed at CERN, while the prototype is in its construction phase. In this contribution, the main features of the D2 magnet will be described, underlining the improvements implemented in the prototype with respect to the short model design. Then, the main results of the power test will be presented, focusing on training performance, protection scheme effectiveness and magnetic measurements.