Multinucleon transfer reactions for the Si28+Zr90,94 systems in the region below and near the Coulomb barrier

Measurements on multinucleon transfer reactions for Si28+Zr90,94 systems were performed at sub- and near-barrier energies. The fact that Zr90 has a closed neutron shell (N = 50) and Zr94 has four neutrons outside the closed shell, allows us to investigate the effects of shell closure and pairing correlation on multinucleon transfer mechanism. The experiment was performed with pulsed Si28 beam using the Heavy Ion Reaction Analyzer (HIRA) at Inter University Accelerator Centre (IUAC), New Delhi. Based on the Q-value considerations, it turned out that pickup channels were neutron transfer whereas stripping channels were proton transfer. For the Si28+Zr90 system, the values of the slope parameter for two-neutron pickup turned out to be less than that for one-neutron pickup. The values of the slope parameter were almost the same for two-, three-, and four-neutron pickup channels in the case of the Si28+Zr94 system. The transfer probabilities in the case of the Si28+Zr94 system were much larger than those for the Si28+Zr90 system, further supporting the fact that there is a correlation between the transfer channels and sub-barrier fusion cross-section enhancement. An odd-even staggering was observed in the extracted transfer probabilities at the barrier radius implying the role of pairing correlation in transfer reactions.