Related papers: Properties of the a0 resonances

The light scalar mesons a_0/f_0(980) are being investigated at COSY-Juelich by detecting the strong decays into K-K-bar and pi-eta/pi-pi as well as radiative decays into vector mesons. Selected results are discussed with emphasis on recent…

It is argued that the single-spin asymmetry in the reaction $\pi^-p\to a_0^0(980)n\to(\eta\pi^0)_S n$ is extremely sensitive to the mixing of the $a^0_0(980)$ and $f_0(980)$ resonances. It is shown that at low momentum transfers (namely, in…

We have made a thorough study of the $D^+ \to \pi^+ \eta \eta $ reaction, recently measured by the BESIII collaboration, which shows an abnormal strength at high invariant masses in the $\pi\eta$ mass distribution. We studied in detail the…

We investigate photoproduction of eta mesons off protons and neutrons within a coupled-channels effective-Lagrangian method which is based on the K-matrix approach. The two-body final channels included are pi-N, eta-N, phi-N, rho-N,…

We present a theoretical study of the $\gamma\gamma \to \pi\eta$ process from the threshold up to 1.4 GeV in the $\pi\eta$ invariant mass. For the s-wave $a_0(980)$ resonance state we adopt a dispersive formalism using a coupled-channel…

Recently the concept of compositeness has been developed so as to distinguish whether interested hadrons are hadronic molecules or not. Here, in terms of compositeness, we investigate $\bar{K} N$ molecular structure of the $\Lambda (1405)$…

The CP Violating asymmetry in Bs mixing (beta_s) is one of the most promising measurements where physics beyond the Standard Model could be revealed. As such, analyses need to be subjected to great scrutiny. The mode Bs -> J/psi\phi has…

Starting from the lowest order chiral Lagrangian for the interaction of the baryon decuplet with the octet of pseudoscalar mesons we find an attractive interaction in the $\Delta K$ channel with L=0 and I=1, while the interaction is…

Initiated by the recent observation of a flattened lineshape of $IJ^{PC}=00^{-+}$ around $1.4\sim 1.5$ GeV in the $K_S K_S \pi^0$ invariant mass spectrum by BESIII, we make a systematic partial wave analysis of $J/\psi \to\gamma\eta_X\to…

A combined analysis of data on isoscalar S-wave processes $\pi\pi\to\pi\pi,K\overline{K},\eta\eta$ and on decays $J/\psi\to\phi\pi\pi,\phi K\overline{K}$ from the DM2, Mark III and BESIII collaborations is performed to study $f_0$ mesons.…

We report the first observation of the Xi- pi+ decay mode of the Xi0(1690), confirming the existence of this resonance. The Xi0(1690) were produced by Sigma- of 345 Gev/c mean momentum in copper and carbon targets. The mass and width are…

The noteworthy BaBar and Belle evidence for $D^0$-$\bar{D}^0$ mixing motivates us to study its impact on $D^0\to K^{*\pm} K^\mp$ decays and their CP-conjugate processes. We show that both the $D^0$-$\bar{D}^0$ mixing parameters ($x$ and…

The $\gamma p \to K^+ \pi^0 \Lambda$ and $\gamma p \to K^+ \pi \Sigma $ reactions are studied in the kinematic region where the $\pi^0 \Lambda$(1116) and $\pi\Sigma$(1192) pairs originate dominantly from the decay of the $\Sigma$(1385) and…

The newly observed $\Xi(1620)^0$ by the Belle Collaboration inspires our interest in performing a systematic study on the interaction of an anti-strange meson $(\bar{K}^{(*)})$ with a strange or doubly strange ground octet baryon…

The photoproduction processes gp-->a0(980)p and gp-->f0(980)p at energies close to threshold are considered. These reactions are studied in the \pi\pi p, \pi\eta p, and K-barK p channels. Production cross sections are estimated in different…

We study $D_{s}^{+}\to\rho^{0(+)}a^{+(0)}_{0}$, $D_{s}^{+}\to\omega a^{+}_{0}$, and the resonant $D_{s}^{+}\to\rho a_0$,$a_{0}\to \eta\pi(KK)$ decays. In the final state interaction, where $D_s^+\to (\eta^{(\prime)}\pi^+,K^+\bar K^0)$ are…

We review our recent dispersive and model independent determination of the lightest two scalars, in terms of poles and residues - or mass, width and coupling- by means of once and twice subtracted Roy equations, using as input constrained…

We use our latest dispersive analysis of pion-pion scattering data and the very recent Kl4 experimental results to obtain the mass, width and couplings of the two lightest scalar-isoscalar resonances. These parameters are defined from their…

The $s-$wave meson-baryon scattering is analyzed for the strangeness S=0 sector in a Bethe-Salpeter coupled channel formalism incorporating Chiral Symmetry. Four channels have been considered: $\pi N$, $\eta N$, $K \Lambda$, $K \Sigma$. The…

We look into the newly observed $\Omega (2012)$ state from the molecular perspective in which the resonance is generated from the $\bar{K} \Xi^*$, $\eta \Omega$ and $\bar{K} \Xi$ channels. We find that this picture provides a natural…