Extraction of nuclear imaginary potential from the excitation function of backward quasi-elastic scattering*

Abstract The nuclear potential is a cornerstone in the study of nuclear structures and reactions. Research on the real part of nuclear potential has been well described using various models; however, that on the imaginary part of nuclear potential remains insufficient. This study proposes a novel method to extract the imaginary nuclear potential from the high-precision excitation function of backward quasi-elastic scattering. The typical systems O Sm, W with deformed target nuclei were analyzed. Nuclear imaginary potentials were obtained successfully by fitting the excitation functions within the single-channel and coupled-channel frameworks, respectively. A good reproduction at the energy range between sub- and above-barrier energy regions was achieved. Results show long-range imaginary-part potential at a wide energy region covering the Coulomb barrier, consistent with the strong absorption for well-deformed systems. This work is a preliminary attempt to bridge the gap between fusion and scattering and extract the deformation parameters in the whole energy range. The subsequent systematic analysis needs to be further improved.