Related papers: Axial vector tetraquark with S=+2
Scalar tetraquark states are studied within the diquark-antidiquark picture in a non-relativistic approach. We consider two types of confining potentials, a quadratic and a linear one, to which we also add spin-spin, isospin-isospin, and…
We investigate the chiral structure of local vector and axial-vector tetraquark currents, and study their chiral transformation properties. We consider the charge-conjugation parity and classify all the isovector vector and axial-vector…
The strong decays of the pseudoscalar and scalar double-charmed tetraquarks $ T_{cc;\overline{u}\overline{d}}^{+}$ and $\widetilde{T}_{cc;\overline{u} \overline{d}}^{+}$ are investigated in the framework of the QCD sum rule method. The mass…
We systematically investigate the S-wave singly heavy tetraquark systems containing two or three strange quarks, $Qs\bar{s}\bar{s}$, $Qn\bar{s}\bar{s}$ and $Qs\bar{s}\bar{n}\left( Q=c,b,n=u,d \right) $, within the constituent quark…
The properties of possibly existing tetraquarks are studied in the large-$N_{\mathrm{c}}^{}$ limit of QCD by means of four-point correlation functions of meson currents.The necessity of a detailed analysis of the singularities of Feynman…
We have calculated the mass spectra for the $\bar{D}_s^{(*)}D^{(*)}$ molecular states and $sc\bar q\bar c$ tetraquark states with $J^P=0^+, 1^+, 2^+$. The masses of the axial-vector $\bar{D}_sD^{*}$, $\bar{D}_s^{*}D$ molecular states and…
In this exploratory study the spectrum of tetraquarks of type $c \bar c s \bar s$ is calculated within a simple quark model with chromomagnetic interaction and effective quark masses extracted from meson and baryon spectra. It is tempting…
We present in this talk recent results of the vector and axial-vector transitions of the nucleon to the pentaquark baryon Theta^{+}, based on the SU(3) chiral quark-soliton model. The results are summarized as follows: K^{*}-N-Theta vector…
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…
Open-heavy tetraquark states, especially those contain four different quarks have drawn much attention in both theoretical and experimental fields. In the framework of the improved chromomagnetic interaction (ICMI) model, we complete a…
In this article, we take the $X(4140)$ as the diquark-antidiquark type $cs\bar{c}\bar{s}$ tetraquark state with $J^{PC}=1^{++}$, and study the mass and pole residue with the QCD sum rules in details by constructing two types interpolating…
Motivated by the enigmatic vector charmonium-like states, we investigate the strong decay behaviors of four kinds of vector tetraquark states, which are possible candidates for the $Y(4660)$, within the framework of three-point QCD sum…
Hexaquarks constitute a natural extension of complex quark systems like also tetra- and pentaquarks do. To this end the current status of $d^*(2380)$ in both experiment and theory is shortly reviewed. Recent high-precision measurements in…
The quark model does not exclude states composed of more than three quarks, like pentaquark systems. Controversial evidence for such states has been published in the last years, in particular: for a strange pentaquark Theta(1540)+; for a…
We propose to search for the open heavy-flavor exotic states with the quark components of $Qs\bar u\bar d$ with $Q=b,c$ via their weak decays. If there exist such exotic states below the $BK$ or $DK$ thresholds, they can only decay weakly.…
In this article, we introduce a relative P-wave to construct the doubly-charm axialvector diquark operator, then take the doubly-charm axialvector (anti)diquark operator as the basic constituent to construct the scalar and tensor tetraquark…
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…
We calculate the widths of the various pentaquarks in a relativistic model in which the pentaquark is considered to be composed of a scalar diquark and a spin 1/2 triquark. We consider both positive and negative parity for the pentaquark.…
A large data set of proton-nucleus collisions at sqrt(s) =41.6 GeV has been searched for Theta+ and Xi(1862) pentaquark candidates. In 2x10**8 inelastic events we find no evidence for narrow signals (sigma=5 MeV/c**2) in the Theta+ --> pK0s…
The observed mass pattern of scalar resonances below 1 GeV gives preference to the tetraquark assignment over the conventional $\bar qq$ assignment for these states. We present a search for tetraquarks with isospins 0, 1/2, 1 in lattice…