Title: Superintegrable relativistic systems in spacetime-dependent background fields,
Abstract: We consider a relativistic charged particle in background electromagnetic
fields depending on both space and time. We identify which symmetries of the
fields automatically generate integrals (conserved quantities) of the charge
motion, accounting fully for relativistic and gauge invariance. Using this we
present new examples of superintegrable relativistic systems. This includes
examples where the integrals of motion are quadratic or nonpolynomial in the
canonical momenta.