arXiv:nucl-th/0404092 · Physical Review A

WKB approximation for multichannel barrier penetrability

K. Hagino, A. B. Balantekin

Published Sep 21, 2004• 85 citations

Abstract

Using the method of the local transmission matrix, we generalize the well-known WKB formula for barrier penetrability to multichannel systems. We compare the WKB penetrability with a solution of the coupled-channels equations, and show that the WKB formula works well at energies well below the lowest adiabatic barrier. We also discuss the eigenchannel approach to a multichannel tunneling, which may improve the performance of the WKB formula near and above the barrier.

DOI: 10.1103/physreva.70.032106

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