Related papers: Coupled channel effects in pion pion S-wave intera…
For coupled channels $D^0K^+$, $D^+K^0$, $D_s^+\eta$, and $D_s^+\pi^0$, the $S$-wave scattering amplitudes are constructed taking into account the mixing of the isoscalar resonance $D^*_{s0}(2317)^+$ with nonresonance amplitudes with…
We investigate $\pi\rho$ scattering based on the coupled-channel formalism with the $\pi\rho$ and $K\bar{K}^*$ ($\bar{K}K^*$) channels included. We construct the kernel amplitudes by using the meson-exchange model and compute the coupled…
The analysis of the poles of the $\pi\pi$ scattering amplitude is shown to favour a dynamical origin of the sigma meson: it is created by a strongly attractive $\pi\pi$ interaction in the $J^{PC}=0^{++}I=0$ channel. In the limit…
Dispersive representations of the pi-pi scattering amplitudes and pion form factors, valid at two-loop accuracy in the low-energy expansion, are constructed in the presence of isospin-breaking effects induced by the difference between the…
The $s-$wave meson-baryon scattering is analyzed for the strangeness $S=-1$ and isospin I=0 sector in a Bethe-Salpeter coupled channel formalism incorporating Chiral Symmetry. Four channels have been considered: $\pi \Sigma$, $\bar K N$,…
The influence of strong $\pi^+\pi^-$ interaction of the behaviour of pionium nS-state wave functions at small distance are investigated both analytically (perturbatively) and so numerically. It is shown that in the whole the accounting of…
The present status of the in-medium invariant $\pi-\pi$ mass distribution in the sigma-meson channel around the threshold is reviewed from the theory side and contrasted with recent experiments on $(\pi,2\pi)$ knock-out reactions. A…
We extend the relativistic field theoretic finite-volume formalism to $N \pi \pi$ scattering states at maximal isospin, $I=5/2$. As in previous work using the relativistic field theory approach, we work to all orders in a generic low-energy…
The formalism developed in Refs.\cite{Guo:2023ecc,Guo:2024zal} that connects integrated correlation function of a trapped two-particle system to infinite volume scattering phase shift is further extended to coupled-channel systems in the…
We study I=0 $d$ wave $\pi\pi$ scattering phase shift using a proper unitarization approach. It is verified that the $f_2(1270)$ resonance corresponds to a twin pole structure: one on the second sheet, another one on the third sheet. Also…
Using newly calculated electromagnetic corrections, we have made a phase shift analysis of experimental data on pi+/- p elastic scattering up to 100 MeV, assuming the effective hadronic interaction to be isospin invariant. The output…
We study s-wave pion-pion ($\pi\pi$) scattering length in lattice QCD for pion masses ranging from 330 MeV to 466 MeV. In the "Asqtad" improved staggered fermion formulation, we calculate the $\pi\pi$ four-point functions for isospin I=0…
We show that the large corrections due to final state interactions (FSI) in the D^+\to \pi^-\pi^+\pi^+, D^+_s\to \pi^-\pi^+\pi^+, and D^+\to K^-\pi^+\pi^+ decays can be accounted for by invoking scattering amplitudes in agreement with those…
We study the $\Lambda(1520)$ resonance in a coupled channel approach involving the $\pi\Sigma(1385)$, $K\Xi(1530)$, $\bar{K}N$ and $\pi\Sigma$ channels. Implementing unitarity in coupled channels, we make an analysis of the relative…
A coupled channel model is used to study the nature of the f0(980) resonance. It is shown that the existence of two poles close to KKbar threshold, as found in many data fits and confirmed here, can be reconciled with the KKbar molecular…
Low energy scattering and bound state properties of the \pi N, \pi\pi and K\pi systems are studied as coupled channel problems using inversion potentials of phase shift data. In a first step we apply the potential model to explain recent…
Elastic pi N scattering and the reaction pi+ p --> K+ Sigma+ are described simultaneously in a unitary coupled-channels approach which respects analyticity. SU(3) flavor symmetry is used to relate the t- and u-channel exchanges that drive…
A new unitarization approach incorporated with chiral symmetry is established and applied to study the $\pi K$ elastic scatterings. We demonstrate that the $\kappa$ resonance exists, if the scattering length parameter in the I=1/2, J=0…
We have developed a model for the N N --> N N pi pi reaction and evaluated cross sections for the different charged channels. The low energy part of those channels where the pions can be in an isospin zero state is dominated by N*…
We have calculated the KK bar --> KK bar scattering amplitude to next to leading order in Chiral Perturbation Theory. Then, making use of a unitarization procedure with one or several coupled channels (\pi\pi, KK bar in our case) we have…