arXiv subjects

Chun-Meng Tang

Publications and source records attributed to Chun-Meng Tang.

5 recordsLinked to original sources

arXiv2025

QCD sum rule predictions on gluonic tetraquark states with $J^{PC}=0^{+-},0^{--}$ and $1^{\pm \pm}$

In this work, we present a systematic calculation of the mass spectrum for tetraquark hybrid states, focusing on the $8_{[c\bar{c}]}\otimes 8_{[G]}\otimes 8_{[c\bar{c}]}$ color configuration, within the framework of QCD sum rules. As an extension of our previous work on $0^{++}$ and $0^{-+}$ states, we now construct 18 distinct interpolating currents with $J^{PC} = 0^{+-}$, $0^{--}$, and $1^{\pm\pm}$. Using operator product expansion (OPE) techniques and including nonperturbative contributions up to dimension six, we obtain key results: for the $0^{+-}$, $1^{--}$, and $1^{-+}$ states, the predicted masses lie in the range of $7.2-7.3$ GeV, while the $1^{+-}$ and $1^{++}$ states have slightly lower masses, between 6.9 and 7.1 GeV. These predictions provide strong support for the possible existence of an $8_{[c\bar{c}]}\otimes 8_{[G]}\otimes 8_{[c\bar{c}]}$ component within the di-$J/\psi$ structure reported by LHCb. Moreover, our analogous calculations for tetrabottom hybrid states yield mass ranges of $19.4-19.5$ GeV (for $0^{+-}$, $1^{--}$, and $1^{-+}$) and $19.2-19.3$ GeV (for $1^{+-}$ and $1^{++}$), offering crucial references for future searches.

hep-ph↗

arXiv2024

A novel configuration of gluonic tetraquark state

Inspired by the experimental measurement of the charmed hadronic state X(6900), we calculate the mass spectra of tetraquark hybrid states with configuration of $[8_{c}]_{Q\bar{Q}} \otimes [8_{c}]_{G} \otimes [8_{c}]_{Q\bar{Q}}$ in color, by virtue of QCD sum rules. The two feasible types of currents with quantum numbers $J^{PC} = 0^{++}$ and $0^{-+}$ are investigated, in which the contributions from operators up to dimension six are taken into account in operator product expansion (OPE). In the end, we find that, in charm sector, the tetracharm hybrid states with quantum number $0^{++}$ has a mass of about $6.98^{+0.16}_{-0.14} \, \text{GeV}$, while $0^{-+}$ state mass is about $7.26^{+0.16}_{-0.15} \, \text{GeV}$. The results overlap with the experimental observations, suggesting potential tetracharm hybrid interpretations. In bottom sector, calculation shows that the masses of tetrabottom hybrid states with quantum numbers $0^{++}$ and $0^{-+}$ are $19.30^{+0.16}_{-0.17} \, \text{GeV}$ and $19.50^{+0.17}_{-0.17} \, \text{GeV}$, respectively, which are left for future experimental confirmation.

hep-ph↗

arXiv2024

Fully Charmed Tetraquark States in $8_{[c\bar{c}]}\otimes8_{[c\bar{c}]}$ Color Structure via QCD Sum Rules

Stimulated by the recent experimental results on the fully-charm tetraquark states, we systematically calculate the mass spectra of the fully-charm tetraquark states in $8_{[c\bar{c}]}\otimes8_{[c\bar{c}]}$ color configuration via QCD sum rules. By constructing nine $8_{[c\bar{c}]}\otimes8_{[c\bar{c}]}$ type currents with quantum numbers $J^{PC}=0^{-+},0^{--},1^{-+},1^{+-},1^{--}$ and $2^{++}$, we perform analytic calculation up to dimension six in the Operator Product Expansion (OPE). We find the fully-charm tetraquark states with $J^{PC}=1^{+-},2^{++}$ lie around 6.48 $\sim$ 6.62 GeV while the fully-charm tetraquark states with $J^{PC}=0^{-+},0^{--},1^{--},1^{-+}$ are about 6.85 $\sim$ 7.02 GeV. Notably, the mass predictions for the $c\bar{c}c\bar{c}$ tetraquarks, specifically those with $J^{PC}=2^{++}$, align with the broad structure identified by LHCb. Moreover, the masses of fully-charm tetraquarks with $J^{PC}=0^{-+}$ and $1^{-+}$ are anticipated to match closely with the mass of X(6900), considering the margin of error. Such findings hint at the presence of some $8_{[c\bar{c}]}\otimes8_{[c\bar{c}]}$ components within the di-$J/\psi$ structures observed by LHCb. The predictions for tetraquark states with $J^{PC}=0^{--},1^{+-},1^{--}$ may be accessible in the future BelleII, Super-B, PANDA, and LHCb experiments.

hep-ph↗

arXiv2023

Mass predictions of triply heavy hybrid baryons via QCD sum rules

In this article, we study the mass spectrum of the low-lying triply heavy hybrid baryon, which consists of three valence heavy quarks in a color octet and one valence gluon, with spin-parity $J^P=(\frac{1}{2})^+$ via QCD sum rules. This is the first study on the triply heavy hybrid baryons in the framework of QCD sum rules. After performing the QCD sum rule analysis, we find that the mass of $cccg$ hybrid baryon lies in $M_{cccg}= 5.91-6.13$ GeV. As a byproduct, the mass of the triply bottom hybrid baryon state is extracted to be around $M_{bbbg}=14.62-14.82$ GeV. The contributions up to dimension eight at the leading order of $α_s$ (LO) in the operator product expansion are taken into account in the calculation. The triply charmed hybrid baryon predicted in this work can decay into one doubly charmed baryon and one charmed meson. Especially, we propose to search for $cccg$ hybrid baryon with $J^{P}= (1/2)^+$ in the P-wave decay channels $Ξ_{cc}^{++} D^0$, $Ξ_{cc}^{+} D^+$, and $Ξ_{ccs}^{+} D_s^+$, which may be accessible in future BelleII, Super-B, PANDA, and LHCb experiments.

hep-ph↗

arXiv2022

Mass Predictions of Vector ($1^{--}$) Double-gluon Heavy Quarkonium Hybrids from QCD Sum Rules

In this work, we study the $1^{--}$ double-gluon charmonium ($\bar{c}ggc$) and bottomonium ($\bar{b} gg b$) hybrids in terms of QCD sum rules. We find that the mass of $\bar{c}ggc$ hybrid lies in $M_{H_{c}}$ = $5.33 \sim 5.90$ GeV, while in the bottom sector the mass of $\bar{b}ggb$ hybrid may be situated in $M_{H_b} = 11.20 \sim 11.68$ GeV. The contributions up to dimension eight at leading order of $α_s$ (LO) in the operator product expansion are taken into account in the calculation. The double-gluon charmonium hybrid meson predicted in this work can decay into a pair of charmed mesons or a pair of charmed mesons together with a light meson. Especially, we propose to search for $\bar{c}ggc$ hybrid with $I^G(J^{PC})= 0^-(1^{--})$ in their decay channels $D \bar{D}/D^* \bar{D}/D^{*} \bar{D}^{*}$ with P wave and $D^* \bar{D}^{*} π/D^* \bar{D}^*η/D \bar{D}ρ/D \bar{D}ω$ with S wave, which may be accessible in Belle II, PANDA, Super-B, GlueX, and LHCb experiments.

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