Development of a 15 T Nb₃Sn Accelerator Dipole Demonstrator at Fermilab

Abstract

A 100-TeV-scale Hadron Collider (HC) with a nominal operation field of at least 15 T is being considered for the post-LHC era, which requires using the Nb <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> Sn technology. Practical demonstration of this field level in an accelerator-quality magnet and substantial reduction of the magnet costs are important requirements for realization of such a machine. Fermilab has started the development of a 15 T Nb <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> Sn dipole demonstrator for a 100-TeV-scale HC. The magnet design is based on optimized 60-mm-aperture four-layer shell-type coils, graded between the inner and outer layers to maximize the performance and reduce the cost. The experience gained during the Nb <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> Sn magnet R&D is applied to various aspects of the magnet design. This paper describes the magnetic and structural designs and parameters of the 15 T Nb <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> Sn dipole demonstrator and the steps toward its fabrication.