CALCULATION OF WAVE-FUNCTIONS IN THE SUBBARRIER REGION USING 1 N EXPANSION/

A method is developed for calculating wave functions in the subbarrier region on the basis 1/n expansion. This method is used to calculate t he asymptotic coefficient c(lp) at the origin. To illustrate the accur acy of the method the results are compared with results of numerical c alculations for power-law potentials, short-range Yukawa potentials, a nd exponential potentials. Calculations ar performed for node-free sta tes and for states with radial quantum number p = 1. The calculated co rrection of order 1/n is shown to considerably increase the accuracy o f 1/n expansion, especially for p = 1 states (at n similar to 1, a zer o-order approximation for such states is only an estimate).