arXiv subjects

Cheng-Xi Liu

Publications and source records attributed to Cheng-Xi Liu.

4 recordsLinked to original sources

arXiv2026

Exploring charmonia $\eta_c(6S,7S)$ in the $\Lambda_c^+\bar{\Lambda}_c^-$ invariant mass spectrum of $B^0 \to K_S^0\Lambda_c^+\bar{\Lambda}_c^-$

We analyze the $B^0 \to K_S^0 \Lambda_c^+ \bar{\Lambda}_c^-$ decay recently observed by the LHCb Collaboration. The $\Lambda_c^+\bar{\Lambda}_c^-$ invariant-mass spectrum exhibits an accumulation near 4.63~GeV, which we investigate together with the accompanying $\Lambda_c^+ K_S^0$ spectrum constrained by the known $\Xi_c(2923)$ and $\Xi_c(2939)$ states. Our amplitude model includes a nonresonant term, the two established $\Xi_c$ contributions, and high-lying charmonium states in the $\Lambda_c^+\bar{\Lambda}_c^-$ channel. Guided by screened Godfrey--Isgur and quark-pair-creation calculations, we test the 4.63~GeV enhancement with a fixed $\eta_c(6S)$ amplitude at $(4629.00, 24.20)$~MeV, {which improves the description of the 4.63~GeV region}, and examine a fixed $\eta_c(7S)$ contribution at $(4718.84, 22.84)$~MeV, which improves the higher-mass region of the spectrum. We also evaluate the $\eta_c(nS) \to \Lambda_c^+ \bar{\Lambda}_c^-$ baryonic decays via a hadron-loop mechanism and estimate the $B^0 \to K_S^0 \eta_c(nS)$ production in naive factorization. Within the narrow width approximation, the fit yields a $\mathcal B(B^0\to K_S^0\eta_c(6S)) \mathcal B(\eta_c(6S)\to\Lambda_c^+\bar{\Lambda}_c^-)$ of about $6.2 \times 10^{-6}$, while the factorization and hadron-loop calculations give rates roughly one to three orders of magnitude lower than the above fitted ratio. These results highlight the need for more precise data and a full amplitude analysis to determine the line shapes and clarify the nature of the higher-mass contribution.

hep-ph↗

arXiv2024

Prospects for observing the missing $2D$ and $1F$ charmonium states around 4 GeV

Our understanding of high-lying states within the charmonium family remains incomplete, particularly in light of recent observations of charmonium states at energies around 4 GeV. In this study, we investigate the spectroscopic properties of several high-lying charmonia, focusing on the $2D$ and $1F$ states. A mass spectrum analysis is conducted, incorporating the unquenched effects. We then present a detailed study of the strong decay properties, including partial decay widths for two-body strong decays permitted by the Okubo-Zweig-Iizuka (OZI) rule. Additionally, we explore the primary radiative decay channels associated with these states. Finally, we discuss the radiative transitions of the $2D$ and $1F$ states via $e^+e^-$ annihilation. Theoretical predictions provided here aim to guide future experimental searches for high-lying charmonium states at facilities such as BESIII, Belle II, LHCb, and the future STCF.

hep-ph↗

arXiv2024

Construction of Isoscalar $2^{-+}$ Mesonic States Inspired by the $X(2600)$ Discovery

The BESIII observation of the $X(2600)$ suggests that one possible assignment for its spin-parity quantum numbers is $J^{PC}=2^{-+}$. This finding motivates us to systematically revisit isoscalar pseudotensor mesonic states through a comprehensive spectroscopic study. In this work, we employ a potential model to calculate the mass spectrum of isoscalar pseudotensor meson states with varying radial quantum numbers. Additionally, we analyze their strong decay behaviors, as allowed by the Okubo-Zweig-Iizuka (OZI) rule, using the quark pair creation model. Our findings yield valuable information about their resonant parameters and partial decay widths, which can aid in identifying the observed isoscalar pseudotensor states when combined with current experimental data. Importantly, we also predict several radial excitations of isoscalar pseudotensor mesons that remain unobserved experimentally. Furthermore, we exclude the $X(2600)$ from being classified as an isoscalar pseudotensor meson, which is critical for elucidating the properties of the $X(2600)$.

hep-ph↗

arXiv2024

Likelihood analysis of the newly observed $f_0(2020)$, $f_0(2330)$, and $f_0(2470)$ in $J/\psi\to \gamma\eta^\prime\eta^\prime$ as high-lying unflavored scalar mesons

Light mesons have always been an important part of the whole hadron family, once inspiring the SU(3) classification of hadrons as a typical example~\cite{Gell-Mann:1964ewy}. Until now, the search for light mesons has been an ongoing task in hadron physics. In particular, with the accumulation of experimental data, more and more light flavor mesons with the masses around 2.2 GeV were found, including the $Y(2175)$ observed in $J/\psi\to \eta \phi f_0(980)$~\cite{BES:2007sqy} and the $X(2370)$ reported in the decay of $J/\psi\to \gamma \eta^\prime \pi^+\pi^-$~\cite{BESIII:2010gmv,BESIII:2019wkp}. These progresses show that there is a chance to construct the light meson family, which is also an effective approach to deepen our understanding of non-perturbative behavior of the strong interaction.

hep-ph↗