Projectile breakup dynamics for $^{6}$Li + $^{59}$Co: kinematical analysis of $\alpha$-$d$ coincidences

TL;DR

This study investigates the breakup mechanisms of $^{6}$Li when colliding with $^{59}$Co at 29.6 MeV, distinguishing between sequential and direct breakup processes through kinematic analysis of alpha-deuteron coincidences.

Contribution

It provides a detailed semiclassical analysis of projectile breakup processes, identifying the timing and distance of breakup events relative to the target, and links these to fusion outcomes.

Findings

Breakup to low-lying continuum is delayed and occurs at large distances.

Direct breakup to high-lying continuum influences fusion processes.

Sequential breakup contributes differently than direct breakup.

Abstract

A study of the kinematics of the $\alpha$-$d$ coincidences in the $^{6}$Li + $^{59}$Co system at a bombarding energy of $E_{lab} = 29.6$ MeV is presented. With exclusive measurements performed over different angular intervals it is possible to identify the respective contributions of the sequential projectile breakup and direct projectile breakup components. A careful analysis using a semiclassical approach of these processes provides information on both their lifetime and their distance of occurrence with respect to the target. Breakup to the low-lying (near-threshold) continuum is delayed, and happens at large internuclear distances. This suggests that the influence of the projectile breakup on the complete fusion process can be related essentially to direct breakup to the $^6$Li high-lying continuum spectrum. %