2D and 3D Conceptual Magnetic Design of the MADMAX Dipole
Valerio Calvelli, Guillaume Dilasser, Walid M. Abd El Maksoud, C. Berriaud, F.P. Juster, J.P. Lottin, A. Madur, F. Nunio, J. M. Rifflet, L. Scola
Abstract
One of the frontier of particle physics beyond the Standard Model is the research of axion-like particles, to explain the absence of CP violation in the strong interaction and to provide dark matter candidates. In the MADMAX (MAgnetized Disk and Mirror AXion) experiment, the principle of axions detection relies on the predicted emission of an electric field, picked up using dielectric disks. The electric field intensity is proportional to the square of the local magnetic field, thus the MADMAX experiment would be set up in a 9 T NbTi dipole magnet, 6.9 m in length with a bore diameter of 1.35 m. The dipole produces a Figure of Merit over the surface of the disks of 100 T <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> m <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> along 2 meters, enough to detect axions with masses in the range of 100 μeV. This paper reports the 2D and 3D conceptual magnetic design of the MADMAX dipole. Starting from the experimental principles, it introduces the design parameters, constraints, and the methodology employed, aiming at minimizing the magnet cost minimizing the cost of the conductor. Then, the 2D and 3D designs are described, focusing in particular on the cross-section resulting from the 2D optimization and the heads optimization in 3D with and without iron, made by coupling a dedicated analytical approach to genetic algorithms.