${\chi }_c$ decays and the gluon content of the ${\eta }^{\prime }$, $\eta$ mesons

Abstract

The large mass of the ${\eta }^{\prime }$ meson indicates that a sizeable gluon component is present in the meson wave function. However, the ${\chi }_{c0}$ and ${\chi }_{c2}$ decays to ${\eta }^{\prime }$ mesons, which proceed via a purely gluonic intermediate state and we would therefore naïvely expect to be enhanced by such a component, are in fact relatively suppressed. We argue that this apparent contradiction may be resolved by a proper treatment of interference effects in the decay. In particular, by accounting for the destructive interference between the quark and gluon components of the ${\eta }^{\prime }$ distribution function, in combination with a model for strange quark mass effects, we demonstrate that the observed ${\chi }_{c(0,2)}\to \eta {(}^{\prime })\eta {(}^{\prime })$ branching ratios can be reproduced for a reasonable gluon component of the ${\eta }^{\prime }$, $\eta$ mesons.

12 pages, 1 figure. Version accepted for publication in PLB

References in corpus (6)

• The Status of Glueballs
• Transition form factors ${\gamma }^{\ast }\gamma \to \eta$ and ${\gamma }^{\ast }\gamma \to {\eta }^{\prime }$ in QCD
• ${\eta }^{\prime }$ meson mass from topological charge density correlator in QCD
• $\eta -{\eta }^{\prime }$ Mixing in the Flavor Basis and Large N
• Strong $D_s^{\ast }{D}_s{\eta }^{(\prime )}$ and $B_s^{\ast }{B}_s{\eta }^{(\prime )}$ vertices from QCD light-cone sum rules
• Aspects of anomalous glue

Cited by in corpus (4)

• Dynamical spin effects in the holographic light-front wavefunctions of light pseudoscalar mesons
• Proton-${\eta }^{\prime }$ interactions at threshold
• Event generators for $\eta /{\eta }^{\prime }$ decays at BESIII
• Form factors for semileptonic $B_c$ decays into ${\eta }^{{(}^{\prime })}$ and Glueball