Beam energy dependence of cross sections of projectile like fragments in¹⁹F+⁸⁹Y reaction

Abstract

Angular distributions of projectile-like fragments (PLFs) have been measured in 19 F+ 89 Y reaction at E lab = 70, 85 and 100 MeV. From the center of mass angular distributions of PLFs, their cross sections have been deduced at these beam energies. Beam energy dependence of the cross sections of PLFs formed in quasi-elastic transfer reactions has been found to be significantly different from those formed in incomplete fusion (massive transfer) reactions. Experimental angular distributions were converted into the plots of the transfer probability versus distance of closest approach to deduce the slope parameter for different transfer channels. Comparison of the slope parameters suggested that the overlap of the projectile and the target nuclei increases with increasing beam energy for a given transfer channel and also with increasing mass transfer at a given beam energy.

Disentangling reaction mechanisms forαproduction in the6Li +209Bi reaction

“…However, in a theoretical study by Udagawa et al for the 181 Ta( 14 N,α) reaction [13], it has been observed that the ICF is not necessarily a peripheral reaction instead it occurs at deep (∼2 fm inside) peripheral region, also the associated angular momentum is less than l cr . In case of 19 F + 89 Y, 66 Zn [36,37], and many other reactions, the experimental ICF cross sections are found to be much higher than the "sum-rule" predictions as energy decreases toward the Coulomb barrier implying that the contribution from < cr could also be present in the observed ICF. So, a modified "sum rule," that extends the angular momentum window toward lower values, has been employed to reproduce the ICF cross sections for 19 F + 66 Zn [37].…”

Quasi-elastic and massive transfer reactions in the16O+89Yreaction at beam energies around ≈4–5 MeV/nucleon

“…Elastic scattering measurements have been carried out at these beam energies to get information about the grazing angle and normalization of cross section data. The present results on PLF cross sections have been compared with those from our earlier measurements in 19 F + 89 Y reaction [23] to investigate the role of α cluster structure. The PLF cross section data from the present measurements have been compared with the calculations of modified sum-rule model [1,2,22].…”

“…At lower beam energies (∼5 MeV/nucleon), the mechanism of incomplete mass transfer is not well understood, particularly the contribution from collision trajectories with different impact parameters as a function of beam energy. Several studies have been carried out in the recent past to investigate the reactions involving incomplete mass transfer at lower beam energies [19][20][21][22][23][24][25]. At energies very close to the entrance channel Coulomb barrier, such reactions are dominated by quasi-elastic transfer (QET) of a few nucleons [26,27].…”