Related papers: Understanding the $f_0(980)$ and $a_0(980)$ masses…
We study some non leptonic and semileptonic decays of $B_s$ meson into a final scalar meson $f_0(980)$ in the fourth quark generation model. Since the $f_0(980)$ meson is dominantly composed of ($s \bar s $) pair, the mixing induced CP…
In this work, we study the branching ratios of B^{0}_{s}\rightarrow a_{0}(980)[ \rightarrow K\overline{K}, \pi\eta]a_{0}(980), B^{0}_{s} \rightarrow f_{0}(980)[ \rightarrow \pi^{+}\pi^{-}, K^{+}K^{-}]f_{0}(980) and B^{0}_{s} \rightarrow…
Light scalar hadrons can be understood as dynamically generated resonances. These arise as `companion poles' in the propagators of quark-antiquark seed states when accounting for meson-loop contributions to the self-energies of the latter.…
A consistent description of the pi0 pi0 invariant mass distribution in the phi(1020) -> f0(980) gamma -> pi0 pi0 gamma decay and the pi0 eta in phi(1020) -> a0(980) gamma -> pi0 eta gamma is suggested. A search for the consequences of the…
We report the first observation of $a^{0}_{0}(980)$-$f_{0}(980)$ mixing in the decays of $J/\psi\to\phi f_{0}(980)\to\phi a^{0}_{0}(980)\to\phi\eta\pi^{0}$ and $\chi_{c1}\to a^{0}_{0}(980)\pi^{0}\to…
We exploit the W-emission process to study the measured weak decay of the D(s,+)(1.9686) meson into f(0)(980) and a positively charged pion. We conclude that the scalar f(0)(980) meson contains mostly strange-antistrange flavors, which is…
The decays $D^0\to d\bar u\,e^+\nu\to a^-_0(980)\, e^+\nu\to\pi^-\eta\, e^+\nu$ and $D^+\to d\bar d\,e^+\nu\to a^0_0(980)\, e^+\nu\to\pi^0\eta\, e^+\nu$ (and the charge conjugated ones) is the direct probe of the two-quark components in 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…
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…
We continue the investigation of mesons in terms of the spectral integral equation initiated before [hep-ph/0510410, hep-ph/0511005] for the $b\bar b$ and $c\bar c$ systems: in this paper we consider the light-quark ($u, d,s$) mesons with…
The mixing angle, mass and couplings of the light scalar mesons $f_0(500)$ and $f_0(980)$ are calculated in the framework of QCD two-point sum rule approach by assuming that they are tetraquarks with diquark-antidiquark structures. The…
When an unstable ordinary quark-antiquark state couples strongly to other low-mass mesons (such as pions, kaons, $D$-mesons, etc.), the quantum fluctuations generated by the decay products dress the bare `seed' $\bar{q}q$ state and modify…
The light scalar meson spectrum is studied using the improved ladder QCD with the UA(1) breaking Kobayashi-Maskawa-'t Hooft interaction by solving the Schwinger-Dyson and Bethe-Salpeter equations. The dynamically generated…
Motivated by several recent data, we test the QCD spectral sum rules (QSSR) predictions based on different proposals (\bar qq, \bar q\bar q qq, and gluonium) for the nature of scalar mesons. In the I=1 and 1/2 channels, the unusual (wrong)…
Electromagnetic and strong hadron processes at low energies are considered in the renormalizable model with the spontaneously broken $U_0(1)\times U(1)\times SU(2)$ gauge symmetry. Calculated radiative widths of vector mesons and effective…
Isospin symmetry breaking is discussed as a tool for studying the nature and production mechanisms of light scalar mesons. We are concerned with isospin breaking effects with an amplitude $\sim\sqrt{m_d-m_u}$ (instead of the usual $\sim…
We show that $\phi$ radiative decays into scalar mesons [$f_0$(975), $a_0$(980)$\equiv S$] can provide important clues on the internal structures of these mesons. Radiative decay widths vary widely: $B.R.=10^{-4}-10^{-6}$ depending on the…
The light scalar mesons below 1 GeV as tetraquark states are studied in the framework of the flux-tube model, the multi-body confinement instead of the additive two-body confinement is used. From the calculated results, we find that the…
We study the decay $\phi\to\gamma K^+K^-$ taking into account the scalar mesons production $\phi\to\gamma(f_0+a_0) \to\gamma K^+K^-$ and the final state radiation. We note that the relative sign between the final state radiation amplitude…
The following topics are considered. 1. Confinement, chiral dynamics and light scalar mesons. 2. $\phi$-meson radiative decays about nature of light scalar resonances. Arguments in favor of the four-quark model of the $a_0(980)$ and…