New hadron configuration: The double-gluon hybrid state

Abstract

This is the first study on the double-gluon hybrid, which consists of one valence quark and one valence antiquark together with two valence gluons. We concentrate on the one with the exotic quantum number $J^{PC}=2^{+-}$ that conventional $\bar{q}q$ mesons can not reach. We apply QCD sum rule method to evaluate its mass to be $2.26_{-0.25}^{+0.20}$ GeV, and study its possible decay patterns. Especially, its three-meson decay patterns are generally not suppressed severely compared to two-meson decay patterns, so the $S$-wave three-meson decay channels $f_1\omega \pi /f_1\rho \pi$ can be useful in identifying its nature, which is of particular importance to the direct test of QCD in the low energy sector.

Comments: 5 pages, 3 figures, 1 table, revised version to be published in PRD