Related papers: Four-Quark Mesons
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…
The harmonic quarks are applied to the analysis of quark structures of long-lived $D$-mesons and $\psi/J$. In the harmonic quark model the quarks of long-lived mesons ($\pi^0$, $\pi^\pm$, $K^\pm$, $K^0$, $B^0$, $B^\pm$) are weakly…
I review a Constituent-Quark-Meson model (CQM) for heavy meson decays, outlining its characteristics and the calculation techniques developed for it. The strength of this effective model is that it enables to evaluate heavy meson decay…
We investigate tensor mesons as quark-antiquark bound states in a fully covariant Bethe-Salpeter equation. As a first concrete step we report results for masses of J^{PC}=2^{++} mesons from the chiral limit up to bottomonium and sketch a…
We revisit holographic mesons in the D4/D6 model to study holographic light vector mesons and the properties of heavy quarkonium in confining and deconfining phases. To treat the light mesons and heavy quarkonium on the same footing, we use…
In the heavy quark and large Nc limits, ordinary (exotic) heavy baryons can be considered as bound states of heavy mesons (anti-mesons)and chiral solitons. In these limits, the heavy mesons (or anti-mesons) and the chiral solitons are…
We consider a heavy quark-antiquark $(q\bar{q})$ pair as a heavy meson in the medium composed of light quarks and gluons. By using the AdS/CFT correspondence, the properties of this system are investigated. In particular, we study the…
Spectral properties of hadrons in nuclear matter are treated in the framework of QCD sum rules. The influence of the ambient strongly interacting medium is encoded in various condensates. Especially, the structure of different four-quark…
In this work we investigate the weak $\Lambda_{b}\to\Lambda_c$ semi-leptonic and non-leptonic decays. The light-front quark model and diquark picture for heavy baryons are adopted to evaluate the $\Lambda_{b}\to\Lambda_c$ transition form…
The masses and vertex functions of heavy and heavy-light mesons, described as quark-antiquark bound states, are calculated with the Covariant Spectator Theory (CST). We use a kernel with an adjustable mixture of Lorentz scalar,…
In this work we study the meson properties in the framework of an effective quark model. We start from the Bethe-Salpeter equation choosing the interaction kernel in nonlocal form with the Gaussian meson vertex function, characterized by a…
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…
We discuss recent results on heavy and light baryon spectroscopy
We evaluate lower bounds on the sum of the up and down quark masses. The bounds follow from the constraints provided by the dispersion relation obeyed by the two--point function of the scalar current density when combined with properties of…
We calculate masses of light and heavy mesons as well as baryons of negative parity containing $u,d,s,c$ and $b$ quarks. It is an extension of our previous work where we had studied the positive parity baryons. We adopt a quark-diquark…
Masses of heavy baryons and tetraquarks are calculated in the relativistic quark model using the heavy-quark--light-diquark and diquark-antidiquark approximations, respectively.
I investigate the bound state problems of lowest-lying mesons and heavy mesons. Chiral symmetry is essential when one consider lowest-lying mesons. Heavy quark symmetry plays an central role in considering the semi-leptonic form factors of…
The mass spectrum of heavy pseudoscalar mesons, described as quark-antiquark bound systems, is considered within the Bethe-Salpeter formalism with momentum-dependent masses of the constituents. This dependence is found by solving the…
With the discovery of a doubly charmed $\Xi_{cc}$ baryon a somewhat forgotten issue of tetraquarks containing two heavy and two light (anti) quarks, ${\cal T}_{QQ}$, triggered theorist's interest. We discuss quark model estimates of ${\cal…
The quark-antiquark bound states are discussed using the relativistic spectator (Gross) equations. A relativistic covariant framework for analyzing confined bound states is developed. The relativistic linear potential developed in an…