Problem of charged particle motion stability in a magnetic trap

The last works devoted to the problem of stability of separate charged particle motion in an axial-symmetric magnetic mirror trap are reviewed. By the semiempirical criterion of nonlinear resonance overlap it is possible to estimate highly accurate the boundary of stochastic motion instability and the velocity of diffusive change of magnetic moment of a particle in the unstable region. The estimates and the results of numerical counting of charged particle trajectories in magnetic traps have been compared