Related papers: Problem of Light Scalar Mesons
Combining the recent lattice calculation of $a_0(1450)$ and $\sigma(600)$ mesons with the overlap fermion in the chiral regime with the pion mass less than $300 {\rm MeV}$, the quenched lattice calculation of the scalar glueball, and the…
Masses of the ground state light tetraquarks are dynamically calculated in the framework of the relativistic diquark-antidiquark picture. The internal structure of the diquark is taken into account by calculating the form factor of the…
The radiative $\phi\to\pi^0\eta\gamma$ decay is discussed emphasizing the effects of the $a_0$(980) scalar resonance which dominates the high values of the $\pi^0\eta$ invariant mass spectrum. In its lowest part, the proposed amplitude…
We study the strong and electromagnetic decay properties of scalar mesons above 1 GeV within a chiral approach. The scalar-isoscalar states are treated as mixed states of quarkonia and glueball configurations. A fit to the experimental…
Corrections to $K_{L}^{0}\rightarrow \pi^{0} \gamma \gamma$ decay induced by scalar meson exchange are studied within chiral perturbation theory. In spite of bad knowledge of scalar-mesons parameters, the calculated branching ratio can be…
The complementarity between Chiral Perturbation Theory and the Linear Sigma Model is exploited to study scalar meson exchange in V->P0P0gamma decays. The recently reported experimental data on phi->pi0pi0gamma, phi->pi0etagamma and…
We study the light scalar mesons a_0(980) and kappa using N_f = 2+1+1 flavor lattice QCD. In order to probe the internal structure of these scalar mesons, and in particular to identify, whether a sizeable tetraquark component is present, we…
We study the semileptonic decays of $D_{s}^{+}$, $D^{+}$, and $D^{0}$ mesons into the light scalar mesons [$f_{0} (500)$, $K_{0}^{\ast} (800)$, $f_{0} (980)$, and $a_{0}(980)$] and the light vector mesons [$\rho (770)$, $\omega (782)$,…
We show that the f_0(980) and a_0(980) states appearing in scattering and production processes can be described quite well by the two-channel Oller-Oset-Pel\'aez (OOP) version of unitarized chiral theories. It is impossible, however, to…
We analyze the recently proposed Spectral Quark Model in the light of Chiral Perturbation Theory in curved space-time. In particular, we calculate the chiral coefficients $L_1, ..., L_{10}$, as well as the coefficients $L_{11}$, $L_{12}$,…
Using effective field theory methods, we discuss the extraction of the mass and width of the scalar mesons f0(980) and a0(980) from the finite-volume spectrum in lattice QCD. In particular, it is argued that the nature of these states can…
We prove that recent data demonstrates unequivocally that the scalar meson $f_0$(980) is mostly composed of $s\bar{s}$ quarks and that the coupling of $f_0$ to photons and mesons is in agreement with the linear sigma model.
We develop a scheme for the extraction of the properties of the scalar mesons $f_0(600)$, $f_0(980)$, and $a_0(980)$ from lattice QCD data. This scheme is based on a two-channel chiral unitary approach with fully relativistic propagators in…
The center-of-gravity rule is tested for heavy and light-quark mesons. In the heavy-meson sector, the rule is excellently satisfied. In the light-quark sector, the rule suggests that the $a_0(980)$ could be the spin-partner of $a_2(1320)$,…
The study of light hadrons is central to the understanding of confinement--a unique property of QCD. The quark model describs mesons as bound states of quarks and antiquarks. LQCD and QCD-motivated models for hadrons, however, predict a…
The role of light scalar meson `$f_0 (600)$' is investigated in nuclear matter in an Effective chiral model in the mean-field approach. For the purpose, we scan the properties of the matter at various saturation densities imposing…
We analyze the electromagnetic and strong decay properties of the light scalars a0(980) and f0(980) within a hadronic molecule interpretation. Both scalars are discussed within a covariant and gauge invariant model which also allows for…
The masses of the S-wave mesons consisting of the light (u,d,s) quarks are calculated within the constituent quark model. The relativistic Schroedinger-like equation with a confining potential is numerically solved for the complete…
We describe the $B^0$ and $B^0_s$ decays into $J/\psi$ $f_0(500)$ and $J/\psi$ $f_0(980)$ by taking into account the dominant process for the weak decay of $B^0$ and $B^0_s$ into $J/\psi$ and a $q \bar q$ component. After hadronization of…
The status of light I=0, J^{PC}=2^{++} and 0^{++} mesons is discussed, particularly the separation of n-nbar and s-sbar states. They fall into a simple scheme except for f_2(1810). A case is made that this has been confused with the…