arXiv subjects

Ru-You Zheng

Publications and source records attributed to Ru-You Zheng.

5 recordsLinked to original sources

arXiv2026

$\Lambda_c N$ correlation functions with leading-order covariant chiral interactions

The $\Lambda_c p$ momentum correlation functions are investigated using $\Lambda_c N$ interactions derived within the covariant chiral effective field theory. Our analysis reveals that the interaction is weakly attractive in the spin-singlet ${}^1S_0$ channel. In contrast, the ${}^3S_1$ channel exhibits a pronounced sensitivity to coupled-channel effects, i.e., the inclusion of $S$--$D$ mixing results in a repulsive $\Lambda_c p$ interaction; its absence leads to a weakly attractive one. Consequently, the spin-averaged correlation function -- dominated by the triplet state weight -- exhibits repulsive behavior when the $S$-- $D$ mixing is present. Furthermore, the source size dependence of the correlation functions is examined, demonstrating that the resulting variations remain experimentally resolvable within the precision of current femtoscopic measurements. A systematic comparison with non-relativistic chiral effective field theory and phenomenological models yields distinct discrepancies in the femtoscopic correlation functions. These findings underscore the capacity of femtoscopy to discriminate between different theoretical descriptions of the $\Lambda_c N$ interaction and provide useful references for upcoming experimental data.

hep-ph↗

arXiv2025

Hypernuclear structure with the new leading order covariant chiral hyperon-nucleon force

We have studied single-$Λ$ finite hypernuclear systems spanning from light to heavy masses, employing a new microscopic Lambda-N interaction derived from in-medium interactions within relativistic Brueckner-Hartree-Fock calculations using the leading-order covariant chiral hyperon-nucleon force. Without any adjustable parameters, we have successfully reproduced the experimental results for the single-Lambda binding energies. Although some discrepancies persist in light hypernuclei, the overall calculated binding energies show excellent agreement with the experimental data, and outperforming other microscopic interactions. This study further demonstrates the validity of the leading-order covariant chiral hyperon-nucleon potential and provides a practical set of microscopic interactions for the Skyrme-Hartree-Fock framework.

nucl-th↗

arXiv2025

In-medium $ΛN$ interactions with leading order covariant chiral hyperon/nucleon-nucleon forces

In-medium $ΛN$ interactions are crucial in hypernuclei and neutron star physics. In this work, we study the in-medium $ΛN$ interaction within the relativistic Brueckner-Hartree-Fock (RBHF) framework, employing the leading-order covariant chiral hyperon/nucleon-nucleon forces for the first time. We demonstrate that a consistent description of both the experimental cross-section data and the `empirical value' of the $Λ$ single-particle potential can be achieved. This contrasts with the majority of studies in the non-relativistic framework, where higher-order two-body chiral forces are typically required. This study offers a new perspective on the in-medium $ΛN$ interactions, urgently needed in relativistic \textit{ab initio} hypernuclear physics studies.

nucl-th↗

arXiv2023

Evolution of $N=20,28,50$ shell closures in the $ 20 \leqslant Z \leqslant 30$ region in deformed relativistic Hartree-Bogoliubov theory in continuum

Magicity, or shell closure, plays an important role in our understanding of complex nuclear phenomena. In this work, we employ one of the state-of-the-art density functional theories, the deformed relativistic Hartree-Bogoliubov theory in continuum (DRHBc) with the density functional PC-PK1, to investigate the evolution of the $N=20,28,50$ shell closures in the $ 20 \leqslant Z \leqslant 30$ region. We show how these three conventional shell closures evolve from the proton drip line to the neutron drip line by studying the charge radii, two-neutron separation energies, two-neutron gaps, quadrupole deformations, and single-particle levels. In particular, we find that in the $ 21 \leqslant Z \leqslant 27$ region, the $N=50$ shell closure disappears or becomes quenched, mainly due to the deformation effects. Similarly, both experimental data and theoretical predictions indicate that the $N=28$ shell closure disappears in the Mn isotopic chain, also predominantly due to the deformation effects. The DRHBc theory predicts the existence of the $N=20$ shell closure in the Ca, Sc, and Ti isotopic chains, but the existing data for the Ti isotopes suggests the contrary, and therefore more investigations are needed.

nucl-th↗

arXiv2023

One-proton emission from 148,149,150,151Lu in the DRHBc plus WKB approach

One-proton radioactivity in 149Lu, the latest identified proton emitter, is studied in the Wentzel-Kramers-Brillouin (WKB) approach with the proton-nucleus potential extracted from the deformed relativistic Hartree-Bogoliubov theory in continuum (DRHBc) for the first time. The predicted half-life turns out to be consistent with the experimental measurement within uncertainties and (almost) independent of the density functionals in the DRHBc theory. Such a microscopic self-consistent calculation reveals that 149Lu is oblately deformed with a quadrupole deformation -0.18, and rules out the possibility of a prolate quadrupole deformation suggested in the nonadiabatic quasiparticle model. We also check the validity of this approach in the description of 150,151Lu and their isomeric states. The deviations of the predicted half-lives from their experimental counterparts are mostly smaller than those of the theoretical studies without considering deformation effects. Furthermore, we predict 148Lu to be a more oblately deformed proton-emitter with a longer half-life than that of 149Lu, which can be checked in the future. Our studies show that the DRHBc plus WKB approach provides a new alternative method to evaluate the half-lives of well-deformed proton emitters.

nucl-th↗