Understanding the onset of incomplete fusion

International Symposium on Entrance Channel Effect on the Reaction Mechanism in Heavy Ion Collisions

Singh, Pushpendra P.^1 ; Yadav, Abhishek^2 ; Sharma, Vijay R.^2 ; Singh, D.P.^2 ; Kumar, R.^3 ; Singh, R.P.^3 ; Muralithar, S.^3 ; Singh, B.P.^2 ; Bhowmik, R.K.^4 ; Prasad, R.^2

Department of Physics, Indian Institute of Technology Ropar, Punjab-140 001, India^1

Accelerator Laboratory, Department of Physics, A. M. University, Aligarh-202 002, India^2

NP-Group, Inter-University Accelerator Center, New Delhi-110 067, India^3

Variable Energy Cyclotron Centre, 1/AF Bidhan Nagar, Kolkata 700 064, India^4

关键词: Energy dependence;    Evaporation residues;    Incident energy;    Incomplete fusion;    Projectile energy;    Projectile structures;    Spin distribution;    Strength function;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/515/1/012021/pdf
DOI  :  10.1088/1742-6596/515/1/012021

来源: IOP

【 摘 要 】

The entrance channel effect on the onset and strength of incomplete fusion (ICF) has been studied in the present work. Several inclusive experiments have been performed to measure the ICF strength function in12C,16O+169Tm systems at near and above barrier energies. Data obtained in these experiments suggest the existence of ICF even at slightly above barrier energies where complete fusion (CF) is supposed to be the sole contributor, and conclusively demonstrate strong projectile structure and energy dependence of ICF. The incomplete fusion strength functions for160,12,13C+159Tb and160,12,13C+181Ta systems are analyzed as a function of projectile α-Q-value at a constant νrel 0.053c. It has been found that one neutron (1n) excess projectile13C (as compared to12C) results in less incomplete fusion contribution due to its relatively large negative α-Q-value. In order to understand the onset of ICF at such low energies, the driving input angular momenta () involved in the production of different evaporation residues have been deduced from the analysis of experimentally measured spin-distributions for the same projectile-target combinations at the same incident energies. Higher -values, imparted into the system in non-central interactions, are found to be responsible for low energy ICF. The ICF-αxn/2αxn channels display involvement of higher -values than that observed in CF-xn/pxn/αxn/2αxn channels at the very same projectile energies. It has been observed that the mean value ofincreases with successively opened ICF channels and incident energy.