Field Quality Analysis of the Separation-Recombination Dipole MBRD for the High-Luminosity Upgrade of LHC

The Main Bending Recombination Dipole (MBRD), or D2, is one of the magnets foreseen by the High-Luminosity upgrade of the Large Hadron Collider (LHC). D2 features a double aperture, Nb-Ti, cos
$\theta$
dipole, with a central field of 4.5 T for a length of 7.78 m, hence with an integrated magnetic field of 35 T
$\cdot$
m, in a 105 mm bore. The project includes the fabrication of a 1.6 m long model, a full-length prototype and six series magnets, two of which are spare. Till now, the short model and the prototype have been successfully constructed and tested in 2020 and 2023, while the series magnets are presently under manufacturing and the warm magnetic measurements of the first built magnet were performed at the end of July 2023. This contribution will report the final field quality analysis of the prototype and the preliminary one of the series magnets, including results of the first measurements at room temperature (RT), a comparison with the ROXIE simulations and the expected field quality at operating conditions.