arXiv subjects

Hao-Song Li

Publications and source records attributed to Hao-Song Li.

17 recordsLinked to original sources

arXiv2025

Axial charges and magnetic moments of the decuplet pentaquark family

We present a systematic calculation of the axial charges and magnetic moments for the decuplet of hidden-charm molecular pentaquarks within the framework of the constituent quark model. Our findings reveal that the axial charges of these states are comparable in magnitude to that of the nucleon. Furthermore, we find that their magnetic moments obey a set of sum rules (denoted the Hao-Song sum rules) which hold for states sharing the same spin-flavor configuration, even in the presence of SU(3) flavor symmetry breaking. These results provide crucial insights into the internal structure and dynamics of multiquark hadrons, offering valuable guidance for future experimental and theoretical investigations.$μ_{P_ψ^{Δ+}}- μ_{P_ψ^{\Delta0}}+μ_{P_{ψs}^{Σ-}}- μ_{P_{ψs}^{Σ+}} +μ_{P_{ψss}^{N0}}- μ_{P_{ψss}^{N-}}=0$, $ μ_{P_ψ^{Δ++}}+μ_{P_ψ^{Δ-}} +μ_{P_{ψsss}^{Λ-}}= 3μ_{P_{ψs}^{\Sigma0}}$.

hep-ph↗

arXiv2025

Masses of hidden-charm pentaquark states with $J^P = \frac{3}{2}^-$

Within the heavy pentaquark chiral perturbation theory, we calculate the chiral corrections for $J^P=\frac{3}{2}^-$ octet hidden-charm pentaquark masses up to next-to-leading order. Taking the LHCb-reported $P_ψ^N(4440)$ and $P_{ψs}^Λ(4459)$ (with $J^P=\frac{3}{2}^-$) as inputs, we predict the other two octet hidden-charm pentaquark states $P_{ψs}^Σ(4483)$ and $P_{ψss}^{N}(4490)$ with $J^P=\frac{3}{2}^-$. The results provide theoretical guidance for the further search of $P_{ψs}^Σ$ and $P_{ψss}^{N}$ in experiments.

hep-ph↗

arXiv2025

Where is the next pentaquark state?

The LHCb Collaboration has observed two types of hidden-charm pentaquark states $P_ψ^N$ and $P_{ψs}^Λ$ since 2015. In this work, we predict two other types of hidden-charm pentaquark states $P_{ψs}^Σ(4367)$ and $P_{ψss}^{N}(4379)$ within the framework of heavy pentaquark chiral perturbation theory. We suggest the LHCb Collaboration to observe $P_{ψss}^{N}(4379)^{-}$ and $P_{ψss}^{N}(4379)^0$ with $J^P=\frac{1}{2}^{-}$ in the $J/ψΞ$ spectrum through amplitude analyses of $Ω_b^- \to J/ψΞ^0 K^-$ decays and $B^- \to J/ψΞ^- \barΛ$ decays.

hep-ph↗

arXiv2024

Radiative decay and axial-vector decay behaviors of octet pentaquark states

In this work, we systematically calculate transition magnetic moments, radiative decay widths, and axial-vector coupling constants of octet hidden-charm molecular pentaquark states with different flavor representations in constituent quark model. We discuss the relations between transition magnetic moments and decay widths for pentaquark states. For octet pentaquark states with the $8_{1f}$ and $8_{2f}$ flavor representations, decay widths of the processes $P_ψ|\frac{3}{2}^-\rangle_{(\frac{1}{2}^+\otimes1^-)}\to P_ψ|\frac{1}{2}^-\rangle_{(\frac{1}{2}^+\otimes0^-)}γ$ and $P_ψ|\frac{1}{2}^-\rangle_{(\frac{1}{2}^+\otimes1^-)}\to P_ψ|\frac{1}{2}^-\rangle_{(\frac{1}{2}^+\otimes0^-)}γ$ are quite close, decay widths of the $P_ψ|\frac{3}{2}^-\rangle_{(\frac{1}{2}^+\otimes1^-)}\to P_ψ|\frac{1}{2}^-\rangle_{(\frac{1}{2}^+\otimes1^-)}γ$ process are close to zero, and we notice that the axial-vector coupling constants of the pentaquark states are generally smaller than that of the nucleon.

hep-ph↗

arXiv2024

Analysis of the hidden-charm pentaquark states based on magnetic moment and transition magnetic moment

In this work, we calculate the magnetic moments of the $P^{N^{0}}_ψ$ states and $P^{Δ^{0}}_ψ$ states with valence quark content $\bar{c}cudd $ in molecular model, diquark-diquark-antiquark model and diquark-triquark model, as well as the transition magnetic moments in the molecular model. At the same time, we also calculate magnetic moments and transition magnetic moments of $P^{Δ^{++}}_ψ$ states and $P^{Δ^{-}}_ψ$ states in the molecular model as additional products. Our results show that in the diquark-diquark-antiquark model, the magnetic moments of $ λ$ excitation state are usually larger than the magnetic moments of $ ρ$ excitation state. We find some interesting proportional relationships between the expressions of transition magnetic moments. The results provide important insights for future experimental observation of hidden-charm pentaquark states and help to distinguish their inner structures. With these efforts, our understanding of the properties for the hidden-charm pentaquark states will become more abundant.

hep-ph↗

arXiv2024

Electromagnetic properties of the $T^+_{cc}$ molecular states

In this work, we discuss the electromagnetic properties of the $S$-wave and $D$-wave $T^+_{cc}$ molecular states, which include the magnetic moments, transition magnetic moments and radiative decay widths. According to our results, the magnetic moment of $T^+_{cc}$ state observed experimentally is $-0.09μ_N$. Meanwhile, we also discuss the relations between the transition magnetic moments of the $S$-wave $T^+_{cc}$ molecular states and the radiative decay widths, and we analyze the proportionality between the magnetic moments of the $T^+_{cc}$ molecular states. These results provide further information on the inner structure of $T^+_{cc}$ molecular states and deepen the understanding of electromagnetic properties of doubly charmed tetraquarks.

hep-ph↗

arXiv2024

Ab initio calculation of molecular pentaquark magnetic moments in heavy pentaquark chiral perturbation theory

We propose a new heavy pentaquark chiral perturbation theory for the recently observed hidden-charm pentaquark states by LHCb Collaboration. With the ab initio constructed chiral Lagrangians, we present a parameter-free calculation of the octet molecular pentaquark magnetic moments up to one-loop level. We improve the quark model description of the data when we include the leading SU(3) breaking effects coming from the one-loop corrections. Without any experimental inputs, our predictions are so simple and unique that we regard them as a theoretical benchmark to be compared with experiments as well as other theoretical models.

hep-ph↗

arXiv2024

Magnetic moments and axial charges of the octet hidden-charm molecular pentaquark family

In this work, we calculate the magnetic moment and axial charge of the octet hidden-charm molecular pentaquark family in quark model. The Coleman-Glashow sum-rule for the magnetic moments of pentaquark family is always fulfilled independently of SU(3) symmetry breaking. In the $ 8_{2f} $ flavor representation, the magnetic moments of hidden-charm molecular pentaquark states with spin configuration $J^{P}=\frac{1}{2}^{-}(\frac{1}{2}^{+}\otimes0^{-})$ are all equal to $μ_{c}=0.38μ_{N}$. The axial charges of octet hidden-charm molecular pentaquark states are quite small compared to the axial charge of nucleon. The axial charges of the pentaquark states with the spin configuration $J^{P}=\frac{1}{2}^{-}(\frac{1}{2}^{+}\otimes0^{-})$ in $8_{2f}$ flavor representation are all zero.

hep-ph↗

arXiv2022

Magnetic moments of the hidden-charm strange pentaquark states

This paper calculates the magnetic moments of the hidden-charm strange pentaquark states with a quantum number of $J^P={\frac{1}{2}}^{\pm}$, ${\frac{3}{2}}^{\pm}$, ${\frac{5}{2}}^{\pm}$, and ${\frac{7}{2}}^{+}$ in the molecular, diquark-diquark-antiquark, and diquark-triquark models, respectively. Numerical results demonstrate that the magnetic moments change for a different spin-orbit coupling with the same model and when involving different models with the same angular momentum.

hep-ph↗

arXiv2022

Chiral corrections to the masses of the doubly heavy baryons

We study the masses of the doubly bottom baryons and the charmed bottom baryons up to $\mathcal{O}\left(p^{3}\right)$ in heavy baryon chiral perturbation theory. For the low-energy constants, $g_{A}$ was determined in the quark model, and we fit to the lattice QCD data to determine $m_{0}$, $c_{1}$, and $c_{7}$. We show the numerical results up to $\mathcal{O}\left(p^{3}\right)$, and our results are compared with other theoretical results.

hep-ph↗

arXiv2021

The magnetic moments and electromagnetic form factors of the decuplet baryons in chiral perturbation theory

We have systematically investigated the magnetic moments and magnetic form factors of the decuplet baryons to the next-to-next-leading order in the framework of the heavy baryon chiral perturbation theory. Our calculation includes the contributions from both the intermediate decuplet and octet baryon states in the loops. We also calculate the charge and magnetic dipole form factors of the decuplet baryons. Our results may be useful to the chiral extrapolation of the lattice simulations of the decuplet electromagnetic properties.

hep-ph↗

arXiv2020

Spin-$\frac{3}{2}$ doubly charmed baryon contribution to the magnetic moments of the spin-$\frac{1}{2}$ doubly charmed baryons

We have systematically investigated the magnetic moments of spin-$\frac{1}{2}$ doubly charmed baryons in the framework of the heavy baryon chiral perturbation theory. In this paper, one loop corrections with intermediate spin-$\frac{1}{2}$ and spin-$\frac{3}{2}$ doubly charmed baryon states are considered. The numerical results are calculated to next-to-leading order: $μ_{Ξ^{++}_{cc}}=0.35μ_{N}$, $μ_{Ξ^{+}_{cc}}=0.62μ_{N}$, $μ_{Ω^{+}_{cc}}=0.41μ_{N}$. Our results may be useful for future experiment and chiral extrapolation of the lattice QCD.

hep-ph↗

arXiv2018

Magnetic moments of the spin-$1\over 2$ singly charmed baryons in chiral perturbation theory

We systematically derive the analytical expressions of the magnetic moments of the spin-$1\over 2$ singly charmed baryons to the next-to-next-to-leading order in the heavy baryon chiral perturbation theory (HBChPT). We discuss the analytical relations between the magnetic moments. We estimate the-low energy constants (LECs) in two scenarios. In the first scenario, we use the quark model and Lattice QCD simulation results as input. In the second scenario, the heavy quark symmetry is adopted to reduce the number of the independent LECs, which are then fitted using the data from the Lattice QCD simulations. We give the numerical results to the next-to-leading order for the antitriplet charmed baryons and to the next-to-next-to-leading order for the sextet states.

hep-ph↗

arXiv2018

Magnetic moments of the spin-${3\over 2}$ doubly heavy baryons

In this work, we investigate the chiral corrections to the magnetic moments of the spin-$3\over 2$ doubly charmed baryons systematically up to next-to-next-to-leading order with the heavy baryon chiral perturbation theory. The numerical results are given up to next-to-leading order: $μ_{Ξ^{*++}_{cc}}=1.72μ_{N}$, $μ_{Ξ^{*+}_{cc}}=-0.09μ_{N}$, $μ_{Ω^{*+}_{cc}}=0.99μ_{N}$. As a by-product, we have also calculated the magnetic moments of the spin-$3\over 2$ doubly bottom baryons and charmed bottom baryons: $μ_{Ξ^{*0}_{bb}}=0.63μ_{N}$, $μ_{Ξ^{*-}_{bb}}=-0.79μ_{N}$, $μ_{Ω^{*-}_{bb}}=0.12μ_{N}$, $μ_{Ξ^{*+}_{bc}}=1.12μ_{N}$, $μ_{Ξ^{*0}_{bc}}=-0.40μ_{N}$, $μ_{Ω^{*0}_{bc}}=0.56μ_{N}$.

hep-ph↗

arXiv2017

Radiative decays of the doubly charmed baryons in chiral perturbation theory

We have systematically investigated the spin-$\frac{3}{2}$ to spin-$\frac{1}{2}$ doubly charmed baryon transition magnetic moments to the next-to-next-to-leading order in the heavy baryon chiral perturbation theory (HBChPT). Numerical results of transition magnetic moments and decay widths are presented to the next-to-leading order: $μ_{Ξ_{cc}^{*++}\rightarrowΞ_{cc}^{++}}=-2.35μ_{N}$, $μ_{Ξ_{cc}^{*+}\rightarrowΞ_{cc}^{+}}=1.55μ_{N}$, $μ_{Ω_{cc}^{*+}\rightarrowΩ_{cc}^{+}}=1.54μ_{N}$, $Γ_{Ξ_{cc}^{*++}\rightarrowΞ_{cc}^{++}}=22.0$ keV, $Γ_{Ξ_{cc}^{*+}\rightarrowΞ_{cc}^{+}}=9.57$ keV, $Γ_{Ω_{cc}^{*+}\rightarrowΩ_{cc}^{+}}=9.45$ keV.

hep-ph↗

arXiv2017

Magnetic moments of the doubly charmed and bottomed baryons

The chiral corrections to the magnetic moments of the spin-$\frac{1}{2}$ doubly charmed baryons are systematically investigated up to next-to-next-to-leading order with heavy baryon chiral perturbation theory (HBChPT). The numerical results are calculated up to next-to-leading order: $μ_{Ξ^{++}_{cc}}=-0.25μ_{N}$, $μ_{Ξ^{+}_{cc}}=0.85μ_{N}$, $μ_{Ω^{+}_{cc}}=0.78μ_{N}$. We also calculate the magnetic moments of the other doubly heavy baryons, including the doubly bottomed baryons (bbq) and the doubly heavy baryons containing a light quark, a charm quark and a bottom quark ($\{bc\}q$ and $[bc]q$): $μ_{Ξ^{0}_{bb}}=-0.84μ_{N}$, $μ_{Ξ^{-}_{bb}}=0.26μ_{N}$, $μ_{Ω^{-}_{bb}}=0.19μ_{N}$, $μ_{Ξ^{+}_{\{bc\}q}}=-0.54μ_{N}$, $μ_{Ξ^{0}_{\{bc\}q}}=0.56μ_{N}$, $μ_{Ω^{0}_{\{bc\}q}}=0.49μ_{N}$, $μ_{Ξ^{+}_{[bc]q}}=0.69μ_{N}$, $μ_{Ξ^{0}_{[bc]q}}=-0.59μ_{N}$, $μ_{Ω^{0}_{[bc]q}}=0.24μ_{N}$.

hep-ph↗

arXiv2017

Decuplet to octet baryon transitions in chiral perturbation theory

We have systematically investigated the decuplet (T) to octet (B) baryon ($T\rightarrow Bγ$) transition magnetic moments to the next-to-next-to-leading order and electric quadruple moments to the next-to-leading order in the framework of the heavy baryon chiral perturbation theory. Our calculation includes the contributions from both the intermediate decuplet and octet baryon states in the loops. Our results show reasonably good convergence of the chiral expansion and agreement with the experimental data. The analytical expressions may be useful to the chiral extrapolation of the lattice simulations of the decuplet electromagnetic properties.

hep-ph↗