arXiv subjects

Sheng-Chao Zhang

Publications and source records attributed to Sheng-Chao Zhang.

4 recordsLinked to original sources

arXiv2026

Search for the low-lying excited baryon $Σ^*(1/2^-)$ through process $Λ^+_c \to ΛK^0 π^+$

Motivated by recent BESIII measurements of the singly Cabibbo-suppressed processes $Λ^+_c \to ΛK^+ π^0$ and $Λ^+_c \to ΛK_S^0 π^+$, we investigate the process $Λ^+_c \to ΛK^0 π^+$ by taking into account the contribution from the low-lying excited baryon $Σ^*(1/2^-)$, dynamically generated via the $S$-wave pseudoscalar meson-octet baryon interaction, as well as from the intermediate resonances $K^*(892)$ and $N(1535)$. Our model successfully reproduces the BESIII $π^+K^0$ invariant mass distribution, and predicts a distinct cusp structure around 1.43~GeV in the $π^+Λ$ invariant mass distribution, which is associated with the predicted $Σ^*(1/2^-)$. Future high-precise measurements of this process at BESIII, Belle~II, and the proposed Super Tau-Charm Facility experiments will be crucial for testing the existence of $Σ^*(1/2^-)$ and advancing our understanding of the light baryon spectrum.

hep-ph↗

arXiv2024

Explore the properties of $Λ(1670)$ in the Cabibbo-favored process $Λ^+_c \to p K^- π^+$ decay

Recently, the Belle and LHCb Collaborations have measured the $Λ^+_c \to p K^- π^+$ decay and reported the $p K^-$ invariant mass distribution, which shows a clear cusp structure around the $ηΛ$ threshold. In this work, we have analyzed this process by considering the triangle mechanism and the $S$-wave pseudoscalar meson-octet baryon interactions within the chiral unitary approach, which dynamically generate the $Λ(1670)$. Our results are in good agreement with the Belle measurements, which implies that the cusp structure around $ηΛ$ threshold could be associated with the $Λ(1670)$ with the molecular nature.

hep-ph↗

arXiv2024

Evidence of the low-lying baryon $Σ^*(1/2^-)$ in the process $Λ_c^+\to ηπ^+Λ$

Motivated by the Belle measurements of the process $Λ_c^+\to ηπ^+Λ$, we investigate this process by considering the contributions from the $Λ(1670)$, $a_0(980)$, and $Σ(1385)$. In addition, we also consider the predicted low-lying baryon $Σ^*(1/2^-)$. Our results involving the $Σ^*(1/2^-)$ are favored by fitting to the Belle data of the $ηΛ$ and $π^+Λ$ invariant mass distributions. Furthermore, we predict the $ηπ^+$ invariant mass distribution and the angular distribution $dΓ/d{\rm cos}θ$, which are significantly different depending on whether or not the contribution from the $Σ^*(1/2^-)$ is considered. Finally, we show that, with the contribution from the $Σ^*(1/2^-)$, the calculated Dalizt plot agrees with the Belle measurements. Future precise measurements of the process $Λ_c^+\to ηπ^+Λ$ could shed further light on the existence of the low-lying $Σ^*(1/2^-)$.

hep-ph↗

arXiv2024

Canonical interpretation of the newly observed $J^P =1^+$ structure $X(2085)$

Inspired by the newly observed $X(2085)$ by the BESIII Collaboration, we study the strong decay behaviors of excited axialvector strange mesons within the quark pair creation model. Our results indicate that the $K_1(1793)/K_1(1861)$ can be regarded as the same $K_1(2P)$ state, and the $K_1(1911)$ is assigned as the $K_1(2P^\prime)$ state. Considering the mass, spin-parity, and decay behaviors, we interpret the newly observed $X(2085)$ as the radially excited $K_1(3P)$ state, which mainly decays into the $ρ(1450) K$, $ω(1420)K$, $πK^*(1410)$, $ρK_1(1270)$, and $ρK^*(892)$ final states. Also, the width of $K_1(3P^\prime)$ state is predicted to be about 300 MeV, which can be searched for by future experiments. We expect that present calculations can help us to better understand the nature of the $X(2085)$ structure.

hep-ph↗