arXiv subjects

Shu-Ming Wu

Publications and source records attributed to Shu-Ming Wu.

5 recordsLinked to original sources

arXiv2025

Decay behavior of hidden-strange hadronic molecular state $N(2270)$

In this article, we systematically discuss the decay patterns of the hidden-strange hadronic molecular state $N(2270)$ which is assumed as an S-wave $K^\astΣ^\ast$ shallow bound state with its possible quantum numbers $J^P$ which are ${1/2}^-$, ${3/2}^-$ and ${5/2}^-$. By using the effective Lagrangian approach and considering pseudo-scalar meson and vector meson exchanges, we have thoroughly calculated and discussed the decay behavior of the $N(2270)$ molecular state, including hadronic and radiative decay and the cutoff dependence, for different $J^P$ values. For all three cases, $K^\ast Λ$, $K^\ast Σ$, and $ρN$ final states are always included as the main decay channels. However, the $K Λ$, $πN$ and $πΔ$ final states exhibit notable differences. These different decay properties will provide valuable guidance for future experimental searches and aid in distinguishing different $J^P$ assumptions and understanding their internal structures.

hep-ph↗

arXiv2024

Algorithms for partial wave amplitudes under covariant $L$-$S$ scheme

With the continuous accumulation of data from hadron collision experiments, efficient Partial Wave Analysis tools are indispensable for constructing a clear hadron spectrum. Currently, automated computations of scattering amplitudes primarily use the helicity scheme and covariant effective Lagrangian method. The automated calculations under the covariant $L$-$S$ scheme, which is one of the commonly used partial wave analysis schemes, have not been fully realized. In this work, we provide a general algorithm for computing partial wave amplitudes under the covariant $L$-$S$ scheme. This will lay the foundation for automated computation of partial wave amplitudes under the covariant $L$-$S$ scheme.

hep-ph↗

arXiv2023

Covariant orbital-spin scheme for any spin based on irreducible tensor

In hadron spectrum physics, the partial wave analysis is a primary method used to extract properties of hadronic resonances. The covariant orbital-spin coupling scheme holds unique advantages over other partial wave methods due to its Lorentz covariant form and determined orbital-spin quantum numbers. This paper presents a general form of the covariant orbital-spin coupling scheme based on the irreducible tensor of the homogeneous proper Lorentz group and its little groups. A systematic procedure for constructing partial wave amplitude in a Lorentz covariant way is provided, which can be applied to both massive and massless particles. Specific examples are also included.

hep-ph↗

arXiv2023

Strange molecular partners of $P_c$ states in $γp\toϕp$ reaction

Based on the high statistical data of the CLAS Collaboration on $γp \to ϕp$ reaction in the center-of-mass energy range of 2.2 GeV to 2.8 GeV, we investigate the possible existence of strange molecular partners of $P_c$ states, i.e., $N^*(2080)$ and $N^*(2270)$ as $K^*Σ$ and $K^*Σ^*$ molecular states. In addition to the t-channel Pomeron exchange, t-channel meson exchange including pseudo-scalar meson $(π,η)$, scalar meson $(σ, a_0(980), f_0(980))$, axial-vector meson $f_1(1285)$, tensor meson $f_2(1270)$, as well as s- and u-channel proton exchange, including s-channel $N^*(2080)$ and $N^*(2270)$ states can fit the data very well. The fitted coupling constants of these $N^*$ molecular states to $pϕ$ and $γp$ are consistent with the results directly calculated from the relevant hadronic triangle diagrams of the molecular picture.

hep-ph↗

arXiv2021

The effective radius for production of baryon-antibaryon pairs from $ψ$ decays

By using the covariant L-S Scheme for the partial wave analysis, we deduce the ratios between the S-wave and D-wave contributions from the recent data of $ψ(1^-) \to B_8(1/2^+) \bar{B}_8(1/2^-)$ from the BESIII collaboration. For the $J/ψ\to Λ\barΛ$ and $J/ψ(ψ(2S))\to Σ^{+}\barΣ^{-}$, the ratios are fixed and the average angular momenta are computed to estimate the effective radii of these processes. The results show that the effective radii of these decays of $J/ψ(ψ(2S))$ are very small, which are around 0.04 fm. Thus, it is a nice place to search excited baryon resonances with lower spin in the decays of $J/ψ(ψ(2S))$. Furthermore, for the other $ψ(1^-) \to B_8(1/2^+) \bar{B}_8(1/2^-)$ reactions, we propose some methods to get such effective radius.

hep-ph↗