Zc+(3900)decay width in QCD sum rules

Abstract

We identify the recently observed charmoniumlike structure Z AE c ð3900Þ as the charged partner of the Xð3872Þ state. Using standard techniques of QCD sum rules, we evaluate the three-point function and extract the coupling constants of the Z þ c J=c þ , Z þ c c þ and Z þ c D þ " D Ã0 vertices and the corresponding decay widths in these channels. The good agreement with the experimental data gives support to the tetraquark picture of this state.

Treating Zc(3900) and Z(4430) as the ground state and first radially excited tetraquarks

“…[24,27,33]: some of their results are shown in Tables IV and V. In Ref. [27] using the threepoint sum rule method and diquark-antidiquark interpolating current authors calculated partial decay width of…”

“…The Z + c (3900) → J/ψπ + ; η c ρ; D +D⋆0 decays' widths were computed in Ref. [27] using the three-point sum rule method, whereas in Ref. [30] widths of the Z + c (3900) → J/ψπ + ; η c ρ decays were found by means of the light cone sum rule (LCSR) approach and a technique of the soft-meson approximation.…”

“…Indeed, there are attempts to treat it as the tightly bound diquark-antidiquark state [27][28][29][30], as the four-quark bound state composed of conventional mesons [31][32][33][34][35][36][37][38][39], or as the threshold cusp [40,41].…”

Magnetic and quadrupole moments of the Zc(3900)

“…Since the mass of Z ± c (3900) is very close to X(3872), it can be advised as the charged partner of the X(3872) in a tetraquark scenario. The properties of the Z ± c (3900) particle have been investigated with different theoretical models and approaches [18][19][20][21][22][23][24][25][26][27][28][29][30][31]. Although the spectroscopic properties of these particles have been studied adequately, the internal structure and nature of the X(3872) and Z ± c (3900) particles have not been fully understood yet.…”

The magnetic moment of the $$Z_c(3900)$$ Z c ( 3900 ) as an axialvector tetraquark state with QCD sum rules

“…Recently, the BESIII collaboration determined the spin and parity of the Z ± c (3900) state to be J P = 1 + with a statistical significance more than 7σ over other quantum numbers in a partial wave analysis of the process e + e − → π + π − J/ψ [4]. If it is really a resonance, the assignments of tetraquark state [5][6][7][8][9][10][11] and molecular state [12][13][14][15][16][17][18][19] are robust according to the non-zero electric charge. The newly observed exotic states X , Y , Z , which are excellent candidates for the multiquark states, provide a good platform for studying the nonperturbative behavior of QCD and attract many interesting works of the particle physicists.…”