Effect of neutron-proton asymmetry on the $^3$H clustering in Boron isotopes

TL;DR

This study examines how neutron-proton asymmetry affects $^{3}$H clustering in Boron isotopes, revealing a non-monotonic trend and proposing SF ratio as a new probe for asymmetric clustering.

Contribution

It introduces a novel analysis of $^{3}$H cluster formation, highlighting the competing effects of neutron skin suppression and asymmetry-driven enhancement.

Findings

$ ext{SF}( ext{$^{3}$H})$ peaks at $^{12}$B.

$ ext{SF}( ext{alpha})$ decreases monotonically with neutron number.

SF ratio serves as a robust observable for asymmetric clustering.

Abstract

To investigate the influence of neutron-proton asymmetry on the formation of asymmetric clusters, we perform a systematic comparative study of $^{3}$H and $\alpha$ cluster preformation in the Boron isotopic chain ($^{11-14}$B). Within the framework of Antisymmetrized Molecular Dynamics (AMD), we compute the nuclear wave functions and subsequently extract the reduced width amplitudes (RWA) and spectroscopic factors (SF). The results show that the $\alpha$ cluster SF exhibits a monotonic decrease with increasing neutron number, consistent with the established suppression effect of the neutron skin. In contrast, the $^{3}$H cluster SF displays a non-monotonic behavior, peaking at $^{12}$B. This distinct trend indicates that the formation of the asymmetric $^{3}$H cluster is subject to a competition between suppression from the neutron skin and an enhancement driven by the neutron-proton asymmetry of the parent nucleus. We successfully isolate this enhancement effect by analyzing the ratio of the SFs, SF($^{3}$H)/SF($\alpha$). This approach not only quantifies the enhancement but also proposes the SF ratio as a robust experimental observable for probing insights into asymmetric clustering phenomena.