Search arXivSearch

arXiv · 2510.24522

Spectrum and electromagnetic properties of $^{24}\mathrm{Mg}$ in the Geometric $α$-cluster Model with $\mathcal{D}_{4h}$ symmetry at leading order

Abstract

The relevance of the point-symmetry group $\mathcal{D}_{4h}$ for the prediction of spectrum and electromagnetic properties of the $^{24}\mathrm{Mg}$ nucleus is discussed in the framework of the geometric $α$-cluster model at leading order. The latter represents a macroscopic $α$-cluster framework wherein nuclear excitations are described in terms of rotations and vibrations of $^4\mathrm{He}$ clusters about their equilibrium positions, at the vertices of a square bipyramid. The finite group associated with the latter regulates the composition of the rotational bands as well as the transitions between the energy levels, by means of additional selection rules, of molecular nature. A sample of reduced electric multipole transition probabilities of intraband nature is provided.

Explore related subjects

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

Gianluca Stellin, Karl-Heinz Speidel. 2025-10-28. Spectrum and electromagnetic properties of $^{24}\mathrm{Mg}$ in the Geometric $α$-cluster Model with $\mathcal{D}_{4h}$ symmetry at leading order. https://arxiv.org/abs/2510.24522

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related papers

Application of the Skyrme Hartree-Fock-Bogoliubov Theory to WIMP-Nucleus Interactions in 40Ar

WIMP scattering from 40Ar is investigated using a self-consistent Skyrme Hartree-Fock-Bogoliubov (HFB) approach. Nuclear form factors relevant to dark matter direct detection are calculated from the resulting one-body density matrix elements and compared with shell-model predictions. Good agreement is found for the spin-independent response, while significant differences are observed for the spin-orbit response due to variations in single-particle occupancies. The effects of particle-number projection are shown to be small for 40Ar. These results demonstrate the sensitivity of certain dark matter response channels to the underlying nuclear structure model and establish a framework for extending mean-field calculations to nuclei beyond the reach of large-scale shell-model studies.

nucl-th

Breakdown of the Plane-Wave Trojan Horse Analysis of the $^{12}\mathrm{C}+{}^{12}\mathrm{C}$ Fusion Reaction: Critical Role of Coulomb Distortions

Recently, a new Trojan Horse Method (THM) measurement of carbon-carbon fusion was reported by Li \textit{et al.} [Phys. Lett. B (2026) 140675]. The purpose of the present work is to demonstrate the breakdown of the plane-wave approximation used in the analysis of these data and the critical role of Coulomb distortions in the initial and final states. The reaction mechanism underlying the THM analysis of the $^{12}\mathrm{C}+{}^{12}\mathrm{C}$ fusion reaction using the $^{16}\mathrm{O}+{}^{12}\mathrm{C}\to α_s+α+{}^{20}\mathrm{Ne}$ reaction is investigated. Particular attention is paid to the spectator momentum distribution and to the dependence of the THM reaction amplitude on the relative carbon-carbon energy $E$. It is demonstrated that agreement with the measured spectator momentum distribution does not by itself validate the plane-wave approximation. Although the experimental momentum distribution can be reproduced, inclusion of Coulomb distortions in both the initial and final channels leads to an energy dependence of the THM amplitude that is completely different from the plane-wave result. Consequently, the energy dependence of the $^{12}\mathrm{C}+{}^{12}\mathrm{C}$ fusion cross section extracted from the THM data can be strongly distorted by the plane-wave treatment. It is concluded that the astrophysical factor extracted in the plane-wave analysis cannot be regarded as reliable and may lead to misleading conclusions concerning the low-energy $^{12}\mathrm{C}+{}^{12}\mathrm{C}$ fusion reaction.

nucl-th