Be-$\alpha$ correlations in the linear-chain structure of C isotopes

TL;DR

This paper explores the structure of excited states in $^{14}$C, revealing how asymmetric configurations of alpha clusters influence neutron distribution and correlations, using a generalized molecular orbital model.

Contribution

It introduces a model incorporating asymmetric alpha cluster configurations to explain neutron correlations in linear-chain states of carbon isotopes.

Findings

Asymmetric 2α+α configurations are favored due to many-body correlations.

Valence neutrons tend to localize around the correlated alpha clusters.

The model provides insights into the structure of $^{16}$C as well.

Abstract

We investigate the linear-chain structures in highly excited states of $^{14}$C using a generalized molecular orbital model, by which we incorporate an asymmetric configuration of three $\alpha$ clusters in the linear-chain states. By applying this model to the $^{14}$C system, we study the $^{10}$Be+$\alpha$ correlation in the linear-chain state of $^{14}$C. To clarify the origin of the $^{10}$Be+$\alpha$ correlation in the $^{14}$C linear-chain state, we analyze linear $3\alpha$ and $3\alpha+n$ systems in a similar way. We find that a linear 3$\alpha$ system prefers the asymmetric 2$\alpha+\alpha$ configuration, whose origin is the many body correlation incorporated by the parity projection. This configuration causes an asymmetric mean field for two valence neutrons, which induces the concentration of valence neutron wave functions around the correlating 2$\alpha$. A linear-chain structure of $^{16}$C is also discussed.