Coupled channel effect in elastic scattering and fusion for ^6,7Li+²⁸Si

¹ Nuclear Physics Division, Saha Institute of Nuclear Physics, Kolkata - 700064, INDIA
² R.K. Mission Vivekananda University, Belur Math, Howrah - 711202, INDIA
³ Nuclear Physics Division, Bhabha Atomic Research Centre, Mumbai - 400085, INDIA
⁴ Departamento de Fìsica Aplicada, Universidad de Huelva, E-21071 Huelva, SPAIN
⁵ Inter-University Accelerator Centre, New Delhi - 110067, INDIA

^a e-mail: mandira.sinha@saha.ac.in

Abstract

The fusion excitation and elastic angular distribution were measured for ^6,7Li+²⁸Si from below to above Coulomb barrier (≤ 3V_b) energies. The barrier distribution derived from the fusion data was found to be broad and asymmetric at the sub-barrier region, compared to 1D BPM estimation. Effect of rotational coupling on fusion was found to be not so dominant. Phenomenological optical potential parameters, with surface and volume type imaginary potentials, were obtained from f tting of elastic scattering data and energy dependence of real and imaginary surface strengths were investigated around the barrier. CDCC calculations considering only breakup of projectile were performed for ^6,7Li+²⁸Si with the elastic scattering data, using the code FRESCO. The effects of breakup of projectile on elastic cross section do not agree with the energy dependence of real and imaginary strength with volume type imaginary potential around the barrier.