Permanent Magnet-Based Quadrupoles for Plasma Acceleration Sources

• DOI: 10.3390/instruments3020027
• Publication Date: 2019-04-24T07:14:28Z
• Authors: Amin Ghaith; Driss Oumbarek; Charles Kitégi; Mathieu Valléau; Fabrice Marteau; Marie-Emmanuelle ...
• Keywords: quadrupoles; [PHYS.PHYS.PHYS-ACC-PH]Physics [physics]/Physics [physics]/Accelerator Physics [physics.acc-ph]; Physics; QC1-999; permanent magnets; [PHYS.PHYS.PHYS-ACC-PH] Physics [physics]/Physics [physics]/Accelerator Physics [physics.acc-ph]; QC770-798; free electron laser; 01 natural sciences; 7. Clean energy; Nuclear and particle physics. Atomic energy. Radioactivity; 0103 physical sciences; laser plasma acceleration

The laser plasma accelerator has shown a great promise where it uses plasma wakefields achieving gradients as high as GeV/cm. With such properties, one would be able to build much more compact accelerators, compared to the conventional RF ones, that could be used for a wide range of fundamental research and applied applications. However, the electron beam properties are quite different, in particular, the high divergence, leading to a significant growth of the emittance along the transport line. It is, thus, essential to mitigate it via a strong focusing of the electron beam to enable beam transport. High-gradient quadrupoles achieving a gradient greater than 100 T/m are key components for handling laser plasma accelerator beams. Permanent magnet technology can be used to build very compact quadrupoles capable of providing a very large gradient up to 500 T/m. We present different designs, modeled with a 3D magnetostatic code, of fixed and variable systems. We also review different quadrupoles that have already been built and one design is compared to measurements.