Angular distributions of ${}^7\mathrm{Li}+{}^{11}$B elastic scattering were measured at $E_{\mathrm{lab}}{(}^7\mathrm{Li})=9.85$, 13.3, 18.3, 23.3, and 28.3 MeV within the angular range of ${\theta }_{\mathrm{c}.\mathrm{m}.}\approx {15}^{\circ }$–${80}^{\circ }$. Optical model potentials have been extracted from these angular distributions and the data available in the literature at $E_{\mathrm{lab}}{(}^7\mathrm{Li})=34$ MeV and $E_{\mathrm{lab}}{(}^{11}\mathrm{B})=44$ MeV to study the gross influences of intricate coupling effects varying with the reaction energy. With fixed geometrical shapes, the strengths of both real and imaginary potentials show a linear decrease with increasing energy, which is different from previous observations.

• Received 7 December 2012

DOI:https://doi.org/10.1103/PhysRevC.87.047601