Exploration on $1n$ halo nucleus $^{19}$C from D-RHFB structure to reaction observables

TL;DR

This paper employs a sophisticated relativistic model to accurately describe the structure and reaction observables of the neutron-rich nucleus $^{19}$C, highlighting the importance of continuum effects and challenging previous assumptions about tensor forces.

Contribution

The study introduces a unified D-RHFB and Glauber model approach that successfully reproduces experimental data and clarifies the ground state properties of $^{19}$C, advancing understanding of halo nuclei.

Findings

Accurately reproduces separation energies and ground state spin-parity of $^{19}$C.

Confirms the halo structure formation is driven by continuum effects.

Shows tensor force components are less influential than previously thought.

Abstract

We utilize the axially deformed relativistic Hartree-Fock-Bogoliubov (D-RHFB) model to describe the structure of neutron-rich carbon isotopes, taking into account the continuum, pairing correlations, tensor force and their interplay. In this scheme, one- and two-neutron separation energies of neutron-rich carbon isotopes agree well with measured data, as well as the spin and parity $J^\pi=1/2^+$ for the ground state of $^{19}$C, which is a long-standing problem for theoretical structure models. With the structure input extracted from the microscopic D-RHFB model, the reaction observables are well described the Glauber model. In particular, this unified approach accurately reproduces the inclusive longitudinal momentum distributions of the breakup reaction $^{19}$C + $^{12}$C at 240 MeV/nucleon, which rule out the possibility of the ground state of $^{19}$C being $J^\pi=3/2^+$. Moreover, the continuum plays a crucial role in the formation of the halo, which is further confirmed by the reaction cross sections and longitudinal momentum distributions. However, the tensor force components carried by the $\pi$-coupling are not as significant as anticipated. Consequently, the D-RHFB + Glauber approach turns out to be a promising tool to search for halo candidates from the structure to the reaction.