https://doi.org/10.1140/epja/s10050-022-00783-x
Regular Article - Experimental Physics
Channel coupling effects in interactions of 
F with 
Zn at energies around the Coulomb barrier
1
Thapar Institute of Engineering & Technology, Patiala, India
2
Inter-University Accelerator Center, New Delhi, India
3
Department of Physics and Astrophysics, University of Delhi, New Delhi, India
Received:
26
April
2022
Accepted:
30
June
2022
Published online:
15
July
2022
The role of nucleon transfer channel coupling on the sub-barrier fusion excitation function has been elusive. Many studies have attributed a significant sub-barrier fusion cross-section enhancement over one-dimensional barrier penetration model (1d-BPM) calculation to nucleon transfer couplings. However, several systems exhibit no such enhancement besides having positive Q-value nucleon transfer channels.The objective is to delve into the role of coupling to various internal degrees of freedom on the fusion excitation functions in interactions of F with Zn. Fusion cross-section measurements are performed at energies 
20 % above to 15 % below the Coulomb barrier using Heavy Ion Reaction Analyzer (HIRA) at Inter-University Accelerator Center (IUAC), New Delhi. Coupled-channel (CC) calculations, including coupling to vibrational states of 
Zn, rotational states of 
F, and nucleon transfer channels are performed. Cross-sections for various transfer channels are calculated to speculate their coupling effects on the fusion excitation functions. The results are compared on a reduced scale with neighboring systems involving F and 
O as the projectile. The sub-barrier fusion cross-sections of F 
Zn systems are enhanced by orders of magnitude compared to the corresponding 1d-BPM calculations. CC calculations performed with CCFULL, including coupling to collective excitations of reactants and pair transfer channel, failed to reproduce the experimental fusion cross-sections. GRAZING calculations show large one nucleon transfer cross-sections relative to other channels for the two systems. CCDEF calculation show that inclusion of coupling to one proton transfer channel is necessary to reproduce the experimental data for both systems.
© The Author(s), under exclusive licence to Società Italiana di Fisica and Springer-Verlag GmbH Germany, part of Springer Nature 2022
