  We study magnetic traps with very high trap frequencies where the spin is
coupled to the motion of the atom. This allows us to investigate how the
Born-Oppenheimer approximation fails and how effective magnetic and electric
fields appear as the consequence of the non-adiabatic dynamics. The results are
based on exact numerical diagonalization of the full Hamiltonian describing the
coupling between the internal and external degrees of freedom. The position in
energy and the decay rate of the trapping states correspond to the imaginary
part of the resonances of this Hamiltonian and are computed using the complex
rotation method.
