Reaction mechanisms in the 6Li+59Co system

Abstract

The reactions induced by the weakly bound 6Li projectile interacting with the intermediate mass target 59Co were investigated. Light charged particles singles and $\alpha$-$d$ coincidence measurements were performed at the near barrier energies E_lab = 17.4, 21.5, 25.5 and 29.6 MeV. The main contributions of the different competing mechanisms are discussed. A statistical model analysis, Continuum-Discretized Coupled-Channels calculations and two-body kinematics were used as tools to provide information to disentangle the main components of these mechanisms. A significant contribution of the direct breakup was observed through the difference between the experimental sequential breakup cross section and the CDCC prediction for the non-capture breakup cross section.Comment: 30 pages, 8 figure

Coupled-Channel Effects in Collisions Between Heavy Ions Near the Coulomb Barrier

“…2. Thess results are consistent with rather low breakup cross sections measured for the 6,7 Li+ 59 Co reactions even at incident energies larger than the Coulomb barrier [39,40,41]. But the coupling of the breakup channel is extremely important for the CDCC analysis of the angular distributions of the elastic scattering [47] as shown in Fig.…”

“…For reactions induced by weakly bound nuclei [16,17,25,26,27,28,39,40,41] and exotic nuclei [18,19,20,21,22,38,42,43,44,45,46], the breakup channel is open and plays a key role in the fusion process near the Coulomb barrier similarly to the transfer-channel coupling described in the previous section. It is therefore appropriate to use the Continuum-Discretized Coupled-Channel (CDCC) approach [47,48,49,50] to describe the influence of the breakup channel in both the elastic scattering and the fusion process at sub-barrier energies.…”

“…A more detailed investigation of the breakup process in the 6 Li+ 59 Co reaction with particle coincidence techniques is now proposed to discuss the interplay of fusion and breakup processes. Coincidence data compared to three-body kinematics calculations reveal a way how to disentangle the contributions of breakup, incomplete fusion and/or transfer-reemission processes [39,40,41]. Fig.…”

“…[39,40,41] by considering the corresponding lifetimes obtained by using a semi-classical approach fully described in a previous publication [39]. We con- clude that the flux diverted from complete fusion to incomplete fusion would arise essentially from DBU processes via high-lying continuum (non-resonant) states of 6 Li; this is due to the fact that both the SBU mechanism and the low-lying DBU processes from low-lying resonant 6 Li states occur at large internuclear distances [39,40,41]. Work is in progress to study incomplete fusion for 6 Li+ 59 Co within a newly developed 3-dimensional classical trajectory model [51].…”

Reaction mechanisms in the6Li+52Cr system

“…after the break up of the projectile one of the fragments, with approximately projectile velocity, interacts with the target leading to a compound system formation. On the other hand, TR would be a one-step process in which there is a transfer of fragment from the projectile to unbound states of the target followed by particle evaporation [11]. The final residual nucleus is same in both cases.…”