Superdiffusion of energetic particles at shocks: A Lévy flight model for acceleration Sophie Aerdker, Lukas Merten, Frederic Effenberger, Horst Fichtner and Julia Becker Tjus A&A, 693 (2025) A15 Published online: 23 December 2024 DOI: 10.1051/0004-6361/202451765