Design and Construction of the SuperKEKB QC1 Final Focus Superconducting Magnets

The construction of SuperKEKB, which consists of 7 GeV electron and 4 GeV positron main rings, is now going on. The final focus superconducting quadrupole magnets in the interaction region have been designed and constructed. From the field qualities of the prototype magnets, the magnet designs were modified, and the manufacturing and assembling methods of the coils were changed to satisfy the design values. The field measurements of the magnets were performed at room temperature, and confirmed that they were acceptable for the beam operation. In the paper, the design and the construction of the final focus quadrupole magnets, QC1, which will be located at the closest position to the beam interaction point, are presented.