Study of elastic and inelastic scattering of ${}^7$Be + ${}^{12}$C at 35 MeV

Abstract

The elastic and inelastic scattering of ${}^7$Be from ${}^{12}$C have been measured at an incident energy of 35 MeV. The inelastic scattering leading to the 4.439 MeV excited state of ${}^{12}$C has been measured for the first time. The experimental data cover an angular range of ${\theta }_{cm}$ = 15${}^{\circ }$-120${}^{\circ }$. Optical model analyses were carried out with Woods-Saxon and double-folding potential using the density dependent M3Y (DDM3Y) effective interaction. The microscopic analysis of the elastic data indicates breakup channel coupling effect. A coupled-channel analysis of the inelastic scattering, based on collective form factors, show that mutual excitation of both ${}^7$Be and ${}^{12}$C is significantly smaller than the single excitation of ${}^{12}$C. The larger deformation length obtained from the DWBA analysis could be explained by including the excitation of ${}^7$Be in a coupled-channel analysis. The breakup cross section of ${}^7$Be is estimated to be less than 10$\%$ of the reaction cross section. The intrinsic deformation length obtained for the ${}^{12}$C${}^{\ast }$ (4.439 MeV) state is ${\delta }_2$ = 1.37 fm. The total reaction cross section deduced from the analysis agrees very well with Wong's calculations for similar weakly bound light nuclei on ${}^{12}$C target.

Comments: 8 pages, 5 figures