QCD axial anomaly enhances the $\eta {\eta }^{\prime }$ decay of the hybrid candidate ${\eta }_1(1855)$

Abstract

We study the hybrid mesons with the exotic quantum number $I^G{J}^{PC}=0^{+}{1}^{-+}$ and investigate their decays into the $\eta {\eta }^{\prime }$, $a_1(1260)\pi$, $f_1(1285)\eta$, $f_1(1420)\eta$, $K^{\ast }(892)\bar{K}$, $K_1(1270)\bar{K}$, and $K_1(1400)\bar{K}$ channels. We find that the QCD axial anomaly enhances the decay width of the $\eta {\eta }^{\prime }$ channel although this mode is strongly suppressed by the small $P$-wave phase space. Our results support the interpretation of the ${\eta }_1(1855)$ recently observed by BESIII as the $\bar{s}sg$ hybrid meson of $I^G{J}^{PC}=0^{+}{1}^{-+}$. The QCD axial anomaly ensures the $\eta {\eta }^{\prime }$ decay mode to be a characteristic signal of the hybrid nature of the ${\eta }_1(1855)$.

8 pages, 2 figures, 1 table, references added, to be published in Chin. Phys. Lett

References in corpus (8)

• Glueballs, Hybrids, Multiquarks. Experimental facts versus QCD inspired concepts
• Hybrid Mesons
• Masses and decay constants of the $\eta$ and ${\eta }^{\prime }$ mesons from lattice QCD
• The I^G J^{PC}=0^+ 1^{-+} Tetraquark State
• The Strong Decay Patterns of the $1^{-+}$ Exotic Hybrid Mesons
• Toward the existence of odderon as a three-gluon bound state
• Two- and three-gluon glueballs of $C=+$
• Mass of $1^{-+}$ four-quark--hybrid mixed states

Cited by in corpus (25)

• An updated review of the new hadron states
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• Review of the low-lying excited baryons ${\Sigma }^{\ast }(1/2^{-})$
• Analysis of the ${\eta }_1(1855)$ as a $K{\bar{K}}_1(1400)$ molecular state
• $1^{-+}$ Hybrid in $J/\psi$ Radiative Decays from Lattice QCD
• Production of the ${\eta }_1(1855)$ through kaon induced reactions under the assumptions that it is a molecular or a hybrid state
• Mass Predictions of Vector ($1^{--}$) Double-gluon Heavy Quarkonium Hybrids from QCD Sum Rules
• Constructing the $J^{P(C)}=1^{-(+)}$ light flavor hybrid nonet with the newly observed ${\eta }_1(1855)$
• On the ${\eta }_1(1855)$, ${\pi }_1(1400)$ and ${\pi }_1(1600)$ as dynamically generated states and their SU(3) partners
• Radiative production and decays of the exotic ${\eta }_1^{\prime }(1855)$ and its siblings
• Investigation of Mass and Decay Characteristics of the All-light Tetraquark
• Fully-strange tetraquark states with the exotic quantum numbers $J^{PC}=0^{+-}$ and $2^{+-}$
• Predictions of the hybrid mesons with exotic quantum numbers $J^{PC}=2^{+-}$
• Light double-gluon hybrid states with the exotic quantum numbers $J^{PC}=1^{-+}$ and $3^{-+}$
• Investigating ${\eta }_1^{\prime }(1855)$ exotic states in $J/\psi \to {\eta }_1^{\prime }(1855){\eta }^{(\prime )}$ decays
• Revealing the inner structure of the newly observed ${\eta }_1(1855)$ via photoproduction
• Faddeev fixed-center approximation to the $\eta K^{\ast }{\bar{K}}^{\ast }$, $\pi K^{\ast }{\bar{K}}^{\ast }$ and $K{K}^{\ast }{\bar{K}}^{\ast }$ systems
• Mixing angle of $K_1(1270/1400)$ and the $K{\bar{K}}_1(1400)$ molecular interpretation of ${\eta }_1(1855)$
• Light tetraquark states with exotic quantum numbers $J^{PC}=2^{+-}$
• Decay properties of light $1^{-+}$ hybrids
• Mass spectrum of the hidden-charm hybrid states via the QCD sum rules
• Proper constituent gluon mass as the final piece to construct hybrid mesons
• Revisit the heavy quarkonium double-gluon hybrid mesons with exotic quantum numbers
• Systematic study of exotic $1^{-+}$ tetraquark spectroscopy