The low coupling parameters and large radial micromotion oscillations (Fig. 
) suggest that crystals in region B are unstable in the absence
of damping. Indeed, in all simulations, crystals in stability region B promptly melted when damping was removed. Melted crystals underwent a
rapid gain in kinetic energy as they passed through the heating phase (see Fig. ,
file 8crBMelt.trp). The kinetic energy stabilized when the particles reached the high-energy Mathieu regime. In region B, the temperatures corresponding to the relatively uncorrelated trajectories of melted crystals--- i.e., the Mathieu regime--- were sometimes extremely high.
For example, the configuration of 8crBMelt.trp has a temperature of 
K after equilibration in the Mathieu
regime.