MODIFIED WKB TRANSMISSION FOR FUSION

In the optical model (OM) approach for fusion, absorption of flux occu ring beyond the barrier position is presented in detail at low energie s. It has been shown that the OM transmission can be well approximated as a sum of the WKB transmission and a long range absorption (LRA) co ntribution. Owing to absence of LRA, the fusion predictions of coupled channel codes based on transmission approach Like the CCFUS code, do not agree with the predictions of complete coupled reaction channel (C RC) calculations based on OM approach using the code FRESCO. The CCFUS code with a modified transmission which includes LRA contribution is shown to be consistent with the CRC results using FRESCO. The static d eformation of the colliding nuclei strongly influences the fusion imag inary potential and therefore the deep sub-barrier fusion cross sectio ns.