Investigating the η1′(1855) exotic state in the J/ψ → η1′(1855)η(′) decays

An analysis of the J/psi -> eta eta' gamma decay by the BESIII collaboration claims the observation of an exotic state eta(1) (1855) with I-G J(PC) = 0(+) 1(-+). To establish its C-parity partner eta(1)' 1(1855) in the picture of the K (k) over bar (1)(1400) molecular state, we propose that J/psi -> eta(1)'(1855)(eta)(()'()) receives the main contributions from the final state interaction of KK*(K+ K*(-), K- K*(+), K-0(k) over bar*(0), and (k) over bar K-0*(0)). Specifically, Kand K* in J/psi -> KK* decays transform as eta(1)'(1855)eta(()'()), by exchanging a K-1(1400). We predict B(J/psi -> eta(1)'(1855)eta) = (6.3(-3.)(+12.6)) x 10(-6), and B(J/psi -> eta(1)'(1855)eta') =(6.5(-4.6)(+6.6)) x 10(-6), which can be studied in the J/psi -> K*(K) over bar*eta(()'()) decays. (c) 2023 The Author(s). Published by Elsevier B.V.

Automated summary

An analysis by the BESIII collaboration claims the observation of an exotic state eta(1) (1855) in the J/psi -> eta eta' gamma decay. To establish its C-parity partner eta(1)' 1(1855) in the molecular state K (k) over bar (1)(1400) picture, they propose that J/psi -> eta(1)'(1855)(eta)(()'()) receives its main contributions from the final state interaction of KK*(K+ K*(-), K- K*(+), K-0(k) over bar*(0), and (k) over bar K-0*(0)). They predict the branching ratios B(J/psi -> eta(1)'(1855)eta) = (6.3(-3.)(+12.6)) x 10(-6) and B(J/psi -> eta(1)'(1855)eta') =(6.5(-4.6)(+6.6)) x 10(-6), which can be studied in the J/psi -> K*(K) over bar*eta(()'()) decays.