Universality of shell-driven fragment formation in quasifission

Determine whether shell-driven fragment formation constitutes a universal mechanism in quasifission or instead reflects the specific dynamics of particular target–projectile combinations.

Background

The paper explains that previous theoretical studies have identified shell effects in quasifission for several individual reactions, particularly the spherical shell closures associated with 208Pb and octupole-deformed shells. However, the existing understanding is described as primarily case-specific, and no systematic study had convincingly established whether shell effects govern quasifission universally across hot-fusion systems.

The unresolved issue is especially motivated by experimental 48Ti-induced reactions that showed no significant shell-related signatures in quasifission mass spectra. The paper investigates a systematic set of hot-fusion reactions and finds common shell-driven patterns for several projectile classes, but the broader question of universality beyond the studied systems remains explicitly unresolved.