Strong decays of theX(2500)newly observed by the BESIII Collaboration

Abstract

Basing on the observation of a new J P C = 0 −+ state, X(2500), in the partial wave analysis of the decay J/ψ → γX → γφφ performed by the BESIII Collaboration, we have evaluated the strong decays of the X(2500) as the 4 1 S0 and 5 1 S0 ss states in the 3 P0 model of meson decay. The predicted total decay width for the 4 1 S0 ss is about 894.5 MeV, and the one for the 5 1 S0 ss is about 271.1 MeV, which is in agreement with the experimental data Γ X(2500) = 230 +64+56 −35−33 MeV. By considering the mass and the total strong decay width of the X(2500), we propose that the X(2500) state can be interpreted as a candidate of the 5 1 S0 ss state.

The possible members of the $$5^1S_0$$ 5 1 S 0 meson nonet

“…Also, both Eqs. (21) and (22) indicate that the η(2320) is mainly the nn, consistent with the π(2360) nearly degenerating with the η(2320), while the X (2500) is mainly the ss, consistent with our previous analysis [6]. Therefore, the η(2320) and X (2500), together with the π(2360), appear to be the convincing 5 1 S 0 states.…”

“…Among these states, the assignments of the π , η, η , and K as the members of the 1 1 S 0 meson nonet and the π(1300), η(1295), η(1475), and K (1460) as the members of the 2 1 S 0 meson nonet have been widely accepted [2]. In our previous works, we suggested that the π(1800), η(1760), X (1835), and K (1830) can be identified as members of the 3 1 S 0 meson nonet [4], the π(2070), η(2100), and η(2225) can be identified as the members of 4 1 S 0 meson [5], and the X (2500) is the mainly ss member of the 5 1 S 0 meson nonet [6], where the mixing of the X (2500) and its isoscalar partner is not considered and other a e-mail: wangen@zzu.edu.cn b e-mail: lidm@zzu.edu.cn members of the 5 1 S 0 meson nonet are not discussed. In this work, we shall address the possible SU(3) multiplet partners of the X (2500).…”

“…The 3 P 0 model has been widely used to study the strong decays of hadrons in literature [4][5][6][23][24][25][26][27][28][29][30][31][32][33][34][35][36][37][38]. In the 3 P 0 model, the meson strong decay takes place by producing a quark-antiquark pair with vacuum quantum number J PC = 0 ++ .…”

“…The yellow band denotes the measured width for the π(2360) [10,11] tic quark model is about 2385 MeV [13], close to the η(2320) mass. In the presence of the X (2500) as the isoscalar member of the 5 1 S 0 meson nonet [6], we shall discuss the possibility of the η(2320) as the isoscalar partner of the X (2500).…”

Strong decays of the higher isovector scalar mesons

“…[25, 26, 31-35, 39, 43-45], and the constituent quark masses are taken to be m u = m d = 330 MeV and m s = 550 MeV, as in Refs. [27,[31][32][33][34][35]39]. We take γ = 7.1 by fitting to the total width of a 0 (1450) as the 1 3 P 0 state.…”