Related papers: Study of Tetraquarks with a simple model
In the framework of the quark delocalization color screening model (QDCSM), we systematically investigate the double-charm and double-strange tetraquark systems $cc\bar{s}\bar{s}$ with two structures: meson-meson and diquark-antidiquark.…
We look for the existence of stable (by strong interactions) tetraquarks, mesons containing two heavy antiquarks and two light quarks, specifically a $|{\bar b}{\bar b}qq\rangle$ state. This state is viewed as two $|{\bar b}q\rangle $…
A complete classification of tetraquark states in terms of the spin-flavor, color and spatial degrees of freedom was constructed. The permutational symmetry properties of both the spin-flavor and orbital parts of the quark-quark and…
The relativistic four-quark equations are found in the framework of coupled-channel formalism. The dynamical mixing of the meson-meson states with the four-quark states is considered. The four-quark amplitudes of the tetraquarks with hidden…
The pentaquark state recently discovered has been studied with three quark models which either fit the nucleon spin structure or the $NN$ scattering. A minimum $\Theta^+$ mass of 1620 MeV is obtained both for the ${1/2}^\pm$ state. The…
We discuss possibility of the existence of tetraquark states made of four quarks in the string (flux tube) model. The new particle is composed of a diquark and an anti-diquark which are connected by a color flux. It is shown that the…
The first results of a new application of the Thomas-Fermi statistical quark model to mesonic matter is presented. Interesting aspects of the theory are discussed, distinguishing such states from baryonic matter. A major motivation of this…
Recent observations by Belle and BESIII of charged quarkonium-like resonances give new stimulus for theoretical investigation of exotic hadrons in general and heavy tetraquarks in particular. We use QED_2, a confining theory, as a model for…
While hidden, singly, doubly, and fully heavy tetraquark states have been experimentally observed, triply heavy tetraquark states remain unconfirmed. We systematically investigate the spectroscopic and decay properties of four triply…
In this talk, multiquarks are studied microscopically in a standard quark model. In pure ground-state pentaquarks the short-range interaction is computed and it is shown to be repulsive. An additional quark-antiquark pair is then…
The analysis of two-ordinary-meson scattering amplitudes in the limit of a large number $N_{\rm c}$ of the colour degrees of freedom of quantum chromodynamics, with suitably decreasing strong coupling and all quarks transforming according…
We present new linear relations among the masses of S-wave tetraquarks with either one flavour ($QQ \bar Q \bar Q$) or two ($QQ\bar q \bar q$). Because the relations are sensitive to the hidden-colour, spin, and spatial degrees of freedom,…
The relativistic six-quark equations are found in the framework of the dispersion relation technique. The approximate solutions of these equations using the method based on the extraction of leading singularities of the amplitudes are…
Typical candidates of open- and hidden-charm tetra-quark mesons are studied through their decays and productions, and are compared with conventional mesons. In addition, it is proposed how to confirm experimentally that they are tetra-quark…
Inspired by the recent observation of a very narrow state, called $T_{cc}^+$, by the LHCb collaboration, the possible bound states and low-lying resonance states of the doubly heavy tetraquark states $cc\bar{u}\bar{d}$ ($T_{cc}$) and…
In this text different theoretical approaches towards multi-quark states are introduced, namely hadrocharmonia, compact tetraquarks and hadronic molecules. The predictions derived from either of them are contrasted with current and possible…
A systematic investigation of $S$-wave triply heavy tetraquark systems with quark content $\bar{b}c\bar{q}c$ and $\bar{c}b\bar{q}b$ $(q = u,\,d,\,s)$, spin-parity quantum numbers $J^P=0^+$, $1^+$, $2^+$ and isospin $I=0,\,\frac{1}{2}$, is…
We perform systematical investigations of heavy flavor tetraquark systems, including fully heavy $QQ\bar Q\bar Q$ ($Q=b,c$), doubly heavy $QQ^{(\prime)}\bar q\bar q$ ($q=u,d$), and singly heavy $Qs\bar q\bar q$ tetraquark systems, within…
Resonances, which are also described as autoionizing or quasi-bound states, play an important role in the scattering of atoms and ions with electrons. The current article is an overview of the main methods, including a recently-proposed…
Fully-heavy tetraquark states, i.e. $cc\bar{c}\bar{c}$, $bb\bar{b}\bar{b}$, $bb\bar{c}\bar{c}$ ($cc\bar{b}\bar{b}$), $cb\bar{c}\bar{c}$, $cb\bar{b}\bar{b}$, and $cb\bar{c}\bar{b}$, are systematically investigated by means of a…