Related papers: Decisive Search for a Diquark-Antidiquark Meson wi…
Models proposed to explain recently discovered heavy-light four-quark states already assume certain internal structures, i.e. the (anti)quark constituents are grouped into diquark/antidiquark clusters, heavy-meson/light-meson clusters…
The molecular assignments to the three $P_c$ states and the similar production mechanism between the $\Lambda_b\to P_c+K$ and $B\to XYZ+K$ convince us the $B$ decaying to a charmonium state plus light mesons could be the appropriate…
Exotic mesons with hidden strange ($s\bar s$) and heavy quark pairs ($Q\bar Q$), where $Q=c,b$, are considered as diquark-antidiquark systems, $(Qs)(\bar Q\bar s)$. Taking into account that these states can recombinate into two-meson ones,…
We analyze the reactions gamma+p => M+B, with M B being either K+ Lambda, K+ Sigma0, or pi+ n, within perturbative QCD, allowing for diquarks as quasi-elementary constituents of baryons. The diquark-model parameters and the quark-diquark…
The strange-anticharmed Pentaquark is a $uud\bar{c}s$ or $udd\bar{c}s$ five-quark baryon that is expected to be either a narrow resonance, or possibly even stable against strong and electromagnetic decay. We describe this hyperon here, its…
QCD-motivated models for hadrons predict an assortment of "exotic" hadrons that have structures that are more complex than the quark-antiquark mesons and three-quark baryons of the original quark-parton model. These include pentaquark…
The reactions gamma p -> K+ Lambda and gamma p -> K* Lambda are analyzed within perturbative QCD, allowing for diquarks as quasi-elementary constituents of baryons. The diquark-model parameters and the quark-diquark distribution amplitudes…
The strange-anticharmed Pentaquark is a uud(cbar)s or udd(cbar)s five-quark baryon that is expected to be either a narrow resonance, or possibly even stable against strong decay. We describe this hyperon here; its structure, binding energy…
Evidences for new baryon states with mass >1.8 GeV were obtained in the experiments of the SPHINX Collaboration in studying hyperon-kaon mass spectra in several proton diffractive reactions. The main result of these experiments is the…
In recent years there has been a rapidly growing body of experimental evidence for existence of exotic, multiquark hadrons, i.e. mesons which contain additional quarks, beyond the usual quark-antiquark pair and baryons which consist of more…
We describe the electroproduction ratios of baryon-meson states from nucleon, inferring from the sea quarks in the nucleon using an extension of the quark model that takes into account the sea. As a result we provide, with no adjustable…
The quark structure of the $f_2(1270)$ meson has, for many years, been assumed to be a pure quark-antiquark ($q\bar{q}$) resonance with quantum numbers $J^{PC} = 2^{++}$. Recently, it was proposed that the $f_2(1270)$ is a molecular state…
We study exotic baryon systems composed of anticharmed mesons and strange baryons using the extended local hidden gauge approach. By solving the coupled-channel Bethe-Salpeter equation with interaction kernels from vector meson exchange, we…
The discovery of some baryon-antibaryon resonances has led us to consider 3q~3\bar{q} systems as possible candidates. We predict their spectrum in the framework of a constituent model, where the chromo-magnetic interaction plays the main…
We present an overview of the description of K and eta meson productions in nucleon-nucleon collisions within an effective Lagrangian model where meson production proceeds via excitation, propagation and subsequent decay of intermediate…
In this talk I show recent results on how many excited baryon resonances appear as systems of one meson and one baryon, or two mesons and one baryon, with the mesons being either pseudoscalar or vectors. Connection with experiment is made…
The state of the art in dibaryons with strangeness is reviewed, including the K^{-}pp dibaryon which signals the onset of antikaon-nuclear binding. A new type of strange dibaryons is highlighted, where the primary binding mechanism is…
Diquark correlations are important in baryons, which can be modeled as quark-diquark bound states. In addition, diquarks could play a role in non-standard hadrons such as tetraquarks and pentaquarks. Here, we obtain properties of these…
We present a new dynamical picture that identifies the formation of the exotic $\bar c c$-containing states $XY \! Z$ with the confinement-induced hadronization of a rapidly separating pair of a compact diquark and antidiquark. This picture…
The recent developments in the search of exotic pentaquark hadrons are briefly reviewed. We then focus on investigating how the exotic pentaquark $\Theta(1540)$ baryon production can be identified in the $\gamma N \to K \bar{K} N$…