Neutron-rich nuclei near the N = 126 shell closure are vital for r -process nucleosynthesis but remain challenging to produce. Multinucleon transfer reactions offer a promising route. We investigate the role of shell effects in such processes by extending the CLIM-H model with a deformation-dependent mass formula and a scaling factor a that linearly adjusts the shell-correction strength. Calculations for 136 Xe on 208 Pb, 204 Hg, and 208 Hg targets reveal a dual role: shell effects enhance few-nucleon transfers near the entrance channel but strongly suppress fragments requiring the transfer of many nucleons, most severely for the doubly magic 208 Pb. This suppression stems from the cumulative transfer probabilities and is aggravated by lower survival after deexcitation. Thus, optimal production of exotic N = 126 nuclei requires avoiding strongly shell-closed collision partners at N = 126 , as exemplified by doubly magic 208 Pb. We propose 238 U + 204 Hg at E c.m. ≃ 1.45 V B as a superior system, predicting significantly enhanced yields.
Dai et al. (Mon,) studied this question.