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

Abstract

We calculate the masses of χ c (3P) states with threshold corrections in a coupled-channel model. The model was recently applied to the description of the properties of χ c (2P) and χ b (3P) multiplets (Ferretti and Santopinto in Phys Lett B 789:550, 2019]. We also compute the open-charm strong decay widths of the χ c (3P) states and their radiative transitions. According to our predictions, the χ c (3P) states should be dominated by the charmonium core, but they may also show small meson-meson components. The X (4274) is interpreted as a cc χ c1 (3P) state. More information on the other members of the χ c (3P) multiplet, as well as a more rigorous analysis of the X (4274)'s decay modes, are needed to provide further indications on the quark structure of the previous resonance.

Quark Structure of the X (4500), X (4700) and χc(4P,5P) States

“…We also discussed the χ c0 (4500) and χ c0 (4700) "mass problem", i.e., the incompatibility between the QM predictions for their masses [28] and the experimental data [1,18,25], by making use of a Coupled-Channel Model (CCM) based on the UQM formalism [26,27]. According to our results for the χ c0 (4500) and χ c0 (4700) masses with threshold/loop corrections, it seems difficult to reconcile the QM predictions with the experimental data, with the possible exception of χ c0 (4P) → χ c0 (4500) or χ c0 (4700).…”

“…We also provide Coupled-Channel Model (CCM) [26,27] predictions for the physical masses 1 of 4P and 5P charmonia, which may serve as a test for the χ c0 (4P, 5P) → X(4500) or X(4700) controversial assignments. According to our CCM results, the introduction of threshold effects can hardly reconcile the Relativized Quark Model (RQM) predictions for the χ c0 (4P, 5P) meson masses [28] with the properties of the experimentally observed X(4500) and X(4700) states [1,18,25].…”

Heavy quark spin partners of the $Y(4260)$ in coupled-channel formalism

“…For the bare-continuum mixing, which is an important dynamical pieces of the UQM, we adopt the widely used 3 P 0 model [21]. In this model, the nonperturbative creation of light quark-antiquark pair is triggered form QCD vacuum with J PC = 0 ++ , which in spectroscopical notation 2S +1 L J can be written as 3 P 0 [18,22]. The interaction Hamiltonian can be expressed as…”

$X$ structures in $B^+\to J/ψϕK^+$ as one-loop and double-triangle threshold cusps

“…Moreover, two structures in the M J/ψK + distribution were interpreted with 1 + cucs tetraquarks Z cs (4000) + and Z cs (4220) + . The X structures have been commonly interpreted with constituent quark models such as charmonium (χ cJ ) [12][13][14][15][16][17][18][19][20][21], hybrid [14], and tetraquark (cscs) . Hadron molecule models were also developed for X(4140) [33,43,44] and X(4274) [45].…”