Investigation of complete and incomplete fusion in the Li7+Sn124 reaction near Coulomb barrier energies

Abstract

The complete and incomplete fusion cross sections for 7 Li+ 124 Sn reaction were measured using online and offline characteristic γ-ray detection techniques. The complete fusion (CF) cross sections at energies above the Coulomb barrier were found to be suppressed by ∼ 26 % compared to the coupled channel calculations. This suppression observed in complete fusion cross sections is found to be commensurate with the measured total incomplete fusion (ICF) cross sections. There is a distinct feature observed in the ICF cross sections, i.e., t-capture is found to be dominant than α-capture at all the measured energies. A simultaneous explanation of complete, incomplete and total fusion (TF) data was also obtained from the calculations based on Continuum Discretized Coupled Channel method with short range imaginary potentials. The cross section ratios of CF/TF and ICF/TF obtained from the data as well as the calculations showed the dominance of ICF at below barrier energies and CF at above barrier energies.

Investigation of neutron transfer in $^{7}$Li+$^{124}$Sn reaction

“…In the studies of fusion with WBPs, the complete fusion (CF) cross sections are found to be suppressed at above barrier energies with respect to predictions of onedimensional barrier penetration model (1DBPM) [1,2]. An interesting observation in these measurements is that the amount of suppression is commensurate with the measured incomplete fusion (ICF) [6,7]. Total fusion * vparkar@barc.gov.in (TF) which is sum of CF and ICF cross sections match with the 1DBPM predictions at above barrier energies [2].…”

“…The single particle states along with Spectroscopic factors (C 2 S) considered in the calculations are given in Table II. For the 7 Li → 6 Li+n transfer, both the 1p 3/2 and 1p 1/2 components of the neutron bound to 6 Li were included with spectroscopic factors of C 2 S = 0.43 and 0.29 respectively, taken from Cohen and Kurath [28]. Similarly for 7 Li+n → 8 Li transfer, both the 1p 3/2 and 1p 1/2 components of the neutron bound to 7 Li were included with spectroscopic factors of C 2 S = 0.98 and 0.056 respectively, taken from Cohen and Kurath [28].…”

“…Various processes such as, elastic scattering, complete and incomplete fusion, inclusive and exclusive breakup, transfer have been studied in reactions around Coulomb barrier energies using WBP [1,2]. In particular, the stable WBPs such as, 6 Li, 7 Li and 9 Be on several targets have been extensively used for such measurements. Many new features have been highlighted from these studies, which were not observed with strongly bound projectiles (SBP).…”

“…There are not many measurements for the neutron transfer cross section with WBPs and data are scarce. [6,10,11,14,16,17,18,19,20,21].…”

“…In many of these nuclei, one or many neutron transfer are found to give quite dominant contribution to the reaction cross section. For example, in the study of 6,8 He+ 65 Cu, 197 Au systems, 2n transfer channel was shown to be dominant [24,25,26].…”