Related papers: A possible assignment for the ground scalar meson …
The mass and decay of the $s\bar{s}$ member of the $1^{3}F_{4}$ meson nonet are investigated in the framework of the Regge phenomenology and the $^{3}P_{0}$ model. We propose, based on the results, that the assignment of the $s\bar{s}$…
In this paper, we analyze the scalar mesons $f_0(980)$ and $f_0(1500)$ from the decays $\bar B^0_s \to f_0(980)\pi^0, f_0(1500)\pi^0$ within Perturbative QCD approach. From the leading order calculations, we find that (a) in the allowed…
There exists a great deal of concrete evidence in favor of the exotic four-quark nature of light scalars. At the same time, the further expansion of the area of the $q^2\bar q^2$ model validity for light scalars on ever new processes seems…
In the heavy quark limit, we establish the Bethe-Salpeter equations for the ground state $QQ^{\prime} \bar u \bar d$ containing one heavy diquark $QQ^{\prime}$ ($Q, Q^{\prime}=b$ or $c$) and one light antidiquark $\bar u \bar d$. We solve…
The structure of the scalar mesons has been a subject of debate for many decades. In this work we look for $\bar{q}q$ states among the physical resonances using an extended Linear Sigma Model that contains scalar, pseudoscalar, vector, and…
In the I=0 sector there are more scalar mesons than can fit in one $q{\bar q}$ nonet. Consequently, many have claimed that there is in fact more than one multiplet, perhaps both $q{\bar q}$ and $qq{\bar {qq}}$. Such proposals require the…
A coupled channel model is used to study the nature of the scalar mesons produced in the decay phi - gamma pi pi. The KKbar molecular picture of f0(980) is found to be in a good agreement with the recent experimental data from SND and…
First radial excitations of the isoscalar and isovector scalar mesons f_0(400-1200), f_0(980) and a_0(980) are investigated in the framework of a nonlocal version of a chiral quark model of the Nambu--Jona-Lasinio type. It is shown that…
We study the eta' to eta pi pi decay within an effective chiral Lagrangian approach in which the lowest lying scalar meson candidates sigma(560) and kappa(900) together with the f0(980) and a0(980) are combined into a possible nonet. We…
We discuss the new state $D_{sJ}(2317)$ discovered by BaBar and demonstrate using QCD inequalities that if indeed the $f_0(980)$ and the new $D_{sJ}(2317)$ ($0^+$) are primarilly made of four quarks that a new I=0 ``$\bar DD$ bound state''…
For the $a_0(1450)$, considered as the $q\bar{q} 1^3P_0$ state, "experimental" tensor splitting, $c_{exp}=(-150\pm 40$) MeV, appears to be in contradiction with conventional theory of fine structure. There is no such discrepancy if the…
The signs and values of the two-photon couplings $F_{M\gamma\gamma}$ of mesons $(M)$ and their couplings $g_{MNN}$ to the nucleon as entering into the $t$-channel parts of the difference of the electromagnetic polarizabilities…
In this write-up, I summarize the analyses on the low-lying scalar mesons I have done recently with my collaborators. I first briefly review the previous analyses on the hadronic processes related to the scalar mesons, which shows that the…
We investigate the characteristics of $\sigma$, $f_{0}(980)$, and $a_{0}(980)$ with the formalism of chiral unitary approach. With the dynamical generation of them, we make a further study of their properties by evaluating the couplings,…
The partial width of the decay channels $f_0(500) \to \pi \pi$, $f_0(980) \to \pi \pi$ and $f_0(980) \to K \bar K$ are calculated using QCD light-cone sum rules method and a technique of the soft meson approximation. The scalar particles…
Within an effective nonlinear chiral Lagrangian framework the substructure of $f_0(1370)$ is studied. The investigation is conducted in the context of a global picture of scalar mesons in which the importance of the underlying connections…
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.…
We have investigated the process $\Lambda_c^+ \to \pi^+\eta n$ by taking into account the contributions from the nucleon resonance $N(1535)$ and the scalar meson $a_0(980)$, which could be dynamically generated by the interaction of the…
We employed the chiral unitarity approach to investigate the decay process $\Xi_c^+ \to \Sigma^+K^+K^-$, by considering that the low lying nucleon resonance $\Xi(1/2^-)$ and the low lying scalar meson $f_0(980)$ and $a_0(980)$ that could be…
The $K^+$ and $K^0$ meson mass difference induces the mixing of the $a^0_0(980)$ and $f_0(980)$ resonances, the amplitude of which, between the $K^+K^-$ and $K^0\bar K^0$ thresholds, is large in magnitude, of the order of $…