Monopole oscillations in light nuclei with a molecular dynamics approach

TL;DR

This paper investigates monopole oscillations in light nuclei using an antisymmetrized molecular dynamics approach, revealing how nuclear structure influences resonance energies and vibrational modes, with implications for understanding nuclear clustering and breakup processes.

Contribution

It introduces a molecular dynamics method to study monopole vibrations in light nuclei, highlighting the role of clustering and comparing results with Hartree-Fock calculations.

Findings

Giant monopole resonance energy in ${}^{40}Ca$ aligns with Hartree-Fock predictions.

Different vibrational frequencies observed in ${}^{12}C$, ${}^{16}O$, and ${}^{24}Mg$ due to clustering.

Potential link between vibrational modes and alpha cluster breakup at high excitation energies.

Abstract

Collective monopole vibrations are studied in the framework of an antisymmetrized version of molecular dynamics as a function of the vibration amplitude. The giant monopole resonance energy in ${}^{40}Ca$ is sensitive to the incompressibility of the effective interaction, in good agreement with complete time-dependent Hartree-Fock calculations. The collective response of ${}^{12}C$, ${}^{16}O$ and ${}^{24}Mg$ is also studied. For these lighter nuclei that have an important contribution of an $\alpha$-clustered component, different frequencies are observed, corresponding to two different types of vibrations associated with breathing and moving of the underlying clusters. Possible connections with direct breakup into $\alpha$ clusters at high excitation energy are discussed.