RESONANT COOLING IN POSITION-DEPENDENT MAGNETIC-FIELDS

We consider the dynamics of a neutral atom of magnetic moment mu in a spatially dependent magnetic field. Interaction with a resonant radio frequency introduces a peculiar nonlinear dynamics for the slow motion of the center of mass. We derive asymptotically exact equations for t he slow dynamics, which ale compared to the numerical solution of the full nonlinear problem. We also calculate the frequency of small oscil lations for resonant trapped motions.