Extreme nuclear shapes examined via Giant Dipole Resonance lineshapes in hot light mass system

TL;DR

This study investigates how alpha clustering affects nuclear shape dynamics by analyzing GDR lineshapes in specific light nuclei reactions, revealing distinct shape behaviors linked to clustering phenomena.

Contribution

It provides the first direct observation of extended prolate deformation in 32S due to alpha clustering, supported by experimental GDR lineshape analysis.

Findings

Non alpha-like 47V undergoes Jacobi shape transition

Alpha cluster 32S shows extended prolate deformation

Deformation linked to orbiting di-nuclear configuration

Abstract

The influence of alpha clustering on nuclear reaction dynamics is investigated using the giant dipole resonance (GDR) lineshape studies in the reactions 20Ne (Elab=145,160 MeV) + 12C and 20Ne (Elab=160 MeV) + 27Al, populating 32S and 47V, respectively. The GDR lineshapes from the two systems are remarkably different from each other. Whereas, the non alpha-like 47V undergoes Jacobi shape transition and matches exceptionally well with the theoretical GDR lineshape estimated under the framework rotating liquid drop model (RLDM) and thermal shape fluctuation model (TSFM) signifying shape equilibration, for alpha cluster 32S an extended prolate kind of shape is observed. This unusual deformation, seen directly via -decay for the first time, is predicted to be due to the formation of orbiting di-nuclear configuration or molecular structure of 16O+ 16O in 32S superdeformed band.