Escape of a particle from two-dimensional potential well

The paper addresses the escape of a classical particle from a two-dimensional potential well. For the case of zero initial velocities, the escape basin on the configuration plane is explored. Numeric findings are analyzed versus analytic predictions. To this point, two complementary approaches are devised. The first one involves analysis of gradient system with potential relief of the considered well. The other analytic approach takes advantage of an appropriate modification of the isolated resonance approximation. The combination of two aforementioned analytic approaches provides an outer boundary for the stability basin. The mechanism of erosion of the predicted stability boundary via the secondary resonances is explored numerically.