Measurements and coupled reaction channels analysis of one- and two-proton transfer reactions for the ${}^{28}$Si $+$ ${}^{90,94}$Zr systems

Measurements and coupled reaction channels analysis of one- and two-proton transfer reactions for the $^{28}$ Si $+$ $^{90, 94}$ Zr systems

Sunil Kalkal, S. Mandal, A. Jhingan, J. Gehlot, P. Sugathan, K. S. Golda, N. Madhavan, Ritika Garg, Savi Goyal, Gayatri Mohanto, Rohit Sandal, Santosh Chakraborty, Shashi Verma, Bivash Behera, G. Eleonora, H. J. Wollersheim, and R. Singh

Phys. Rev. C 85, 034606 – Published 15 March 2012

Abstract

Measurements of angular distributions for one- and two-proton stripping reactions for $^{28}$ Si $+$ $^{90, 94}$ Zr systems were performed at 120 MeV. The experiment was carried out with the $^{28}$ Si beam at Inter University Accelerator Center, New Delhi. The theoretical calculations were performed using the quantum mechanical coupled reaction channels code fresco. The distorted wave Born approximation calculations reproduced the experimental angular distributions for the one-proton transfer channel for both the systems reasonably well but failed for the two-proton transfer channel. Coupled channels calculations including various intermediate states (involving target and projectile inelastic excitations before and/or after transfer) along with the sequential transfer were able to reproduce the two-proton transfer angular distributions for both the systems reasonably well. It seems that at an energy above the Coulomb barrier, there is significant contribution of the indirect multistep and sequential transfer to the two-proton stripping reaction.