Related papers: Multiquark States
We review various inequalities on the order and the spacing of energy levels, wave function at the origin, etc... which were obtained since 1977 in the framework of the Schrodinger equation and applied to quarkonium and also to muonic atoms…
The light quark $uds$ mesons have been a foundation of our understanding of the strong interaction for decades. New experiments with modern detectors and large data sets are furthering our understanding of the spectrum and dynamics of these…
Light-baryon resonances (with u,d, and s quarks in the SU(3) classification) fall on Regge trajectories. When their squared masses are plotted against the intrinsic orbital angular momenta {\rm L}, $\Delta^*$'s with even and odd parity can…
It is shown that the instanton-induced interaction in qq pairs, iterated in t-channel, leads to a meson-exchange interactions between quarks. In this way one can achieve a simultaneous understanding of low-lying mesons, baryons and the…
Beyond the spontaneous chiral symmetry breaking scale light and strange baryons should be considered as systems of three constituent quarks with an effective confining interaction and a flavor-spin chiral interaction that is mediated by the…
Van der Waals potentials describing interactions between color-singlet mesons and/or baryons vanish at leading order in potential nonrelativistic quantum chromodynamics (pNRQCD). This result and constraints from Gauss's law are used to…
Scalar mesons are a key expression of the strong physics regime of QCD and the role condensates, particularly $<q{\bar q}>$, play in breaking chiral symmetry. What new insights have been provided by recent experiments on $D, D_s$ and…
The $q\bar q$ spectrum is studied in a generalized constituent quark model constrained in the study of the $NN$ phenomenology and the baryon spectrum. An overall good fit to the available experimental data is obtained. A detailed analysis…
The ${q}\bar{q}$ spectrum is studied within a chiral constituent quark model. It provides with a good fit of the available experimental data from light (vector and pseudoscalar) to heavy mesons including some recent results on charmonium.…
In theoretical hadron physics mesons are a center of attention. Constructed in a simpler way than baryons in the quark model, they still present a considerable challenge if one aims at an understanding of all their aspects in terms of…
The coupling to light mesons leads to large widths and shifts of the energy of the excited states in the baryon spectrum from the predictions of the constituent quark model with three valence quarks. This coupling may be modelled by…
Heavy-light mesons, heavy quarkonium and doubly heavy baryons are briefly discussed. Effective field theories (EFTs) of QCD based on the heavy quark mass expansion 1/m_Q provide a unified framework to describe all three systems. They…
We use a bag model to study flavoured mesonic $(Qq\bar q\bar q)$ and baryonic $({\overline Q}qqqq)$ states, where one heavy quark $Q$ is associated with light quarks or antiquarks, and search for possible stable multiquarks. No bound state…
We study the propagation of non-strange and strange meson modes in hadronic matter considering both isospin and strangeness mixings induced by quantum fluctuations in the medium. Baryons are described using the Quark Meson Coupling model…
The $\Delta^{++}$ and the $\Omega^-$ baryons have been used as the original reason for the construction of the Quantum Chromodynamics theory of Strong Interactions. The present analysis relies on the multiconfiguration structure of states…
Inspired by the observation of hidden-charm pentaquark $P_c$ and $P_{cs}$ states by the LHCb Collaboration, we explore the $qqc\bar{c}c$ ($q~=~u$ or $d$) pentaquark systems in the quark delocalization color screening model. The interaction…
A previous work establishing a connection between a quark model, with relativistic kinematics and a $Y$-confinement plus one gluon exchange, and the $1/N_c$ expansion mass formula is extended to strange baryons. Both methods predict values…
We present a plausible mechanism for the origin of the $XYZ$ mesons in the heavy meson spectra within a standard quark-model picture. We discuss the conditions required for the existence of four--quark bound states or resonances…
We present an unquenched quark model for baryons in which the effects of the quark-antiquark pairs (up, down and strange) are taken into account in an explicit form via a microscopic, QCD-inspired, quark-antiquark creation mechanism. In the…
In this work, we systematically investigate the charmed-strange dibaryon systems with $csssqq$ quarks and their baryon-antibaryon partners from the interactions $\Xi^{(',*)}_{c}\Xi^{(*)}$, $\Omega^{(*)}_c\Lambda$,…