Related papers: Towards a Stringy Description for the $Q\bar Q q\b…
In the framework of the color-magnetic interaction model, we have systematically calculated the mass splittings for the S-wave triply heavy pentaquark states with the configuration $qqQQ\bar{Q}$ $(Q=c,b;q=u,d,s)$. Their masses are estimated…
We derive general covariant coupled equations of QCD describing the tetraquark in terms of a mix of four-quark states $2q2\bar q$, and two-quark states $q\bar q$. The coupling of $2q2\bar q$ to $q\bar q$ states is achieved by a simple…
Using variational methods, we numerically investigate the matrix model for the two-color QCD coupled to a single quark (matrix-QCD$_{2,1}$) in the limit of ultra-strong Yang-Mills coupling ($g =\infty$). The spectrum of the model has…
We numerically investigate the transition of the static quark-antiquark string into a static-light meson-antimeson system. Improving noise reduction techniques, we are able to resolve the signature of string breaking dynamics for Nf=2…
The effective quark Lagrangian is written for a light quark in the field of a static antiquark, explicitly containing field correlators as coefficient functions of products of quark operators. At large N_c the closed system of equations for…
Through gravity/gauge duality, the string breaking and running coupling constant of heavy quark-antiquark pair are investigated in the rotating background. For the meson decay mode $\rm Q\bar{Q} \rightarrow Q \bar{q}+\bar{Q} q$, we discuss…
This paper is devoted to the study of exclusive charm and bottom aggregates which are suitable, at least partially, for a non-relativistic description. Starting from a simple choice of quarkonia and tetra-quark wave functions we study their…
The masses of the ground state and excited heavy tetraquarks with hidden charm and bottom are calculated within the relativistic diquark-antidiquark picture. The dynamics of the light quark in a heavy-light diquark is treated completely…
Four-quark states with different internal clusters are discussed within the constituent quark model. It is pointed out that the diquark concept is not meaningful in the construction of a tetraquark interpolating current in the QCD sum rule…
In the framework of QCD Sum Rules we investigate the $q q^\prime \bar{Q} \bar{Q}$ tetraquark structure with quantum number $J^P = 1^+$, which are embedded in two types of configurations, the $[8_c]_{q \bar{Q}} \otimes [8_c]_{q^\prime…
We have recently studied hidden-charm pentaquarks, $c\bar c qqq$, using dynamical correlations between the heavy quarks arising from the Coulomb-like nature of the short-range interaction. A pattern was obtained that compares well with the…
We perform the detailed study of the tetraquark (4Q) potential $V_{\rm 4Q}$ for various QQ-$\rm \bar{Q}\bar{Q}$ systems in SU(3) lattice QCD with $\beta=6.0$ and $16^3 \times 32$ at the quenched level. For about 200 different patterns of 4Q…
We have improved our previous variational method based constituent quark model by introducing a complete set of 3-dimensional harmonic oscillator bases as the spatial part of the total wave function. To assess the validity of our approach,…
The spectra of some 0++ four-quark states, which are composed of \bar qq pairs, are calculated in QCD. The light four-quark states are calculated using the traditional sum rules while four-quark states containing one heavy quark are…
Using the QCD string theory, we investigate the physical reason of the narrow width of penta-quark baryons in terms of the large gluonic-excitation energy. In the QCD string theory, the penta-quark baryon decays via a gluonic-excited state…
We study the tetraquark states with I^G J^{PC}=1^- 1^{-+} in the QCD sum rule. After exhausting all possible flavor structures, we analyses both the SVZ and finite energy sum rules. Both approaches lead to a mass around 1.6 GeV for the…
Many of the $XYZ$ resonances observed by the Belle, Babar, CLEO and BESIII collaborations in the past decade are difficult to interpret as conventional quark-antiquark mesons, motivating the consideration of scenarios such as multi-quark…
The generalization of the effective action [1] of the quark--antiquark system in the confining vacuum is performed for the case of arbitrary quark masses. The interaction of quarks is described by the averaged Wilson loop for which we use…
Inspired by the observed $X(2900)$, we study systematically the mass spectra of the ground pentaquark states with the $qqqq\bar{Q}$ ($Q=c,b$; $q=n,s$; $n=u,d$) configuration in the framework of the Chromomagnetic Interaction model. We…
In this work, we systematically study the mass spectrum of the fully heavy tetraquark in an extended chromomagnetic model, which includes both color and chromomagnetic interactions. Numerical results indicate that the energy level is mainly…