Unambiguous separation of low-energy fusion processes of weakly bound nuclei

Abstract

This paper addresses the critical importance of an unambiguous separation of the different components of the total fusion cross-section, which is a great theoretical and experimental challenge, in order to make further progress in the field of low-energy fusion of weakly bound nuclei. Recent theoretical developments in this area are reviewed. Calculations based on a classical dynamical reaction model indicate that the contribution of sequential fusion to the complete fusion cross-section is very substantial. A toy quantum model is presented, which introduces position projection operators. These can be useful for a quantitative understanding of complete and incomplete fusion of weakly bound nuclei within a more realistic quantum model.

Low-energy fusion dynamics of weakly bound nuclei: A time dependent perspective

“…For this system, the ICF has also been studied with the PLATYPUS model, as reported in Refs. [8,9]. PLATYPUS provides useful information (angular momentum and excitation energy distributions) on the primary ICF products along with differential cross sections of the surviving breakup fragment [9].…”

“…[8,9]. PLATYPUS provides useful information (angular momentum and excitation energy distributions) on the primary ICF products along with differential cross sections of the surviving breakup fragment [9]. The interaction between the fusing fragment and the survival fragment is very important, as this interaction affects both the angular momentum and kinetic energy brought by the captured fragment into the target.…”

“…A quantum dynamical approach is being developed [9] using the timedependent wave-packet (TDWP) method. This model can deal with quantum tunneling, making it possible to investigate the interplay of breakup and fusion at sub-Coulomb energies.…”

“…the 6 Li fragments ( 4 He and 2 H) are always on a line [9]. X CM denotes the distance between the target and the center of mass of the projectile, whereas ξ gives the distance between the projectile fragments.…”

“…Analysis. A limitation of most fusion models of weakly bound nuclei is the lack of an unambiguous calculation of σ CF and σ ICF [9]. We think that a key idea to overcome this problem is to examine the location of each fragment with respect to the position of the individual Coulomb barriers, irrespective of the internal excitation of the 6 Li projectile: if a fragment is located inside the radius of its Coulomb barrier it is considered captured by the target.…”