Low energy incomplete fusion and its relevance to the synthesis of super heavy elements

¹ NP Group: Inter-University Accelerator Centre, Aruna Asaf Ali Marg, New Delhi - 110 067, Delhi, India
² Department of Physics, Aligarh Muslim University, Aligarh - 202 002, Uttar Pradesh, India
³ Department of Physics, University of Petroleum and Energy Studies, Dehradoon - 248 007, Uttrakhand, India
⁴ Department of Physics, Indian Institute of Technology Ropar, Roopnagar - 140 001, Punjab, India
⁵ Department of Physics, Agra College, Agra - 282 001, Uttar Pradesh, India
⁶ Department of Physics, S. V. College, Aligarh - 202 001, Uttar Pradesh, India

^a e-mail: abhishekyadav117@gmail.com

Published online: 29 January 2015

Abstract

To study the presence of incomplete fusion at energies around the Coulomb-barrier and to understand its dependence on various entrance-channel parameters, the incomplete fusion fractions have been deduced (i) from excitation function measurements for ¹⁸O,^13,12C+¹⁵⁹Tb, and (ii) from forward recoil range measurements for ¹²C+¹⁵⁹Tb systems, at low energies (<7MeV/A). The data have been analyzed within the framework of compound nucleus decay, which suggests the production of xn/pxn-channels via complete fusion, as these are found to be well reproduced by PACE4 predictions, while, a significant enhancement in the excitation functions of α-emitting channels has been observed over the theoretical ones, which has been attributed due to the incomplete fusion processes. Further, the incomplete fusion events observed in case of forward recoil ranges have been explained on the basis of the breakup fusion model, where these events may be attributed to the fusion of ⁸Be and/or ⁴He from ¹²C projectile to the target nucleus. For better insight into the underlying dynamics, the deduced fractions of incomplete fusion have been compared with other nearby systems as a function of various entrance channel parameters. The incomplete fusion has been found to be sensitive to the projectile’s energy and alpha-Q-value of the projectile.