Multi-Target Lattice for Muon Production From e⁺ Beam Annihilation on Target

The Low Emittance Muon Accelerator (LEMMA) aims at producing small emittance muons from positron annihilation with electrons in a target. Given the low cross section of the production process, a large number of positrons on the target are required, exposing it to high power deposition and the beam to large degradation because of multiple scattering and bremstrahlung. A multi-target IP, and multi-IP line has been studied to reduce the power deposition per target and the degradation of the positron beam while preserving the number of muon pairs produced. The lattice copes with the focusing and transport of three beams at two different energies, the positron beam at 45 GeV, and + and − beams at 22.5 GeV. Studies on the beam dynamics, number of targets, material and thickness of the targets are reported in this paper.