Tetraquarks with hidden charm and strangeness as ϕ−ψ(2S) hadrocharmonium

Abstract

In the hadrocharmonium picture acc state and a light hadron form a bound state. The effective interaction is described in terms of the chromoelectric polarizability of thecc state and energymomentum-tensor densities of the light hadron. This picture is justified in the heavy quark limit, and may successfully account for a hidden-charm pentaquark state recently observed by LHCb. In this work we extend the formalism to the description of hidden-charm tetraquarks, and address the question of whether the resonant states observed by LHCb in the J/ψ-φ spectrum can be described as hadrocharmonia. This is a non-trivial question because nothing is known about the φ meson energy-momentum-tensor densities. With rather general assumptions about energymomentum-tensor densities in the φ-meson we show that a ψ(2S)-φ bound state can exist, and obtain a characteristic relation between its mass and width. We show that the tetraquark X(4274) observed by LHCb in J/ψ-φ spectrum is a good candidate for a hadrocharmonium. We make predictions which will allow testing this picture. Our method can be generalized to identify other potential hadrocharmonia.

Hidden-charm and bottom tetra- and pentaquarks with strangeness in the hadro-quarkonium and compact tetraquark models

“…Hadro-quarkonia are heavy-light tetra-or pentaquark configurations, where a compact Q Q state (with Q = c or b), labelled as ψ in the following, is embedded in light hadronic matter, H = qqq or q q (where q = u, d or s) [12,[45][46][47][48][49][50][51][52][53][54][55]. The heavy and light constituents, ψ and H, develop an attractive force, which is the result of multiple-gluon exchange between them.…”

“…Therefore, hidden-charm and bottom tetraquark states with non-null strangeness content cannot take place neither in the UQM [13][14][15][16][17][18][19][20][21][22][23] nor in the molecular model [24][25][26][27][28][29] interpretations. On the contrary, these exotic configurations are expected (if above threshold) both in the compact tetraquark [30][31][32][33][34][35][36][37][38][39][40][41][42][43][44] and hadro-quarkonium [12,[45][46][47][48][49][50][51][52][53][54][55] models. See Fig.…”

Quark structure of the $$\chi _{\mathrm{c}}(3P)$$ and X(4274) resonances and their strong and radiative decays

“…Finally, in Ref. [100] the authors suggested to assign the X (4274) to a ψ(2S)φ S-wave hadrocharmonium configuration.…”

The strong coupling $g_{X J/ψϕ}$ of $X(4700) \to J/ψϕ$ in the light-cone sum rules

“…However, the J/ψ − φ potential was found too weak, in lattice QCD, to form a bound states [7]. Furthermore, the Ψ(2S) − φ bound state has already been assigned to X(4274) [8] so that rules out the possibility that X(4700) be a s-wave Ψ(2S) − φ bound state. Anyway, X(4700) could be other hadrocharmonium states in specific regions of the parameter space.…”