Related papers: Pion--Pion Scattering Experiments at Low Energy
Use of the effective Lagrangian incorporating both the scalar and pseudoscalar mesons gives a possibility to calculate the $\pi \pi$-scattering lengths without attraction of the ChPT theory.
Theory and prospects of Compton scattering on nucleons and light nuclei below 500 MeV are outlined; cf. Refs. [1-3]. Invited contribution at the Workshop to Explore Physics Opportunities with Intense, Polarized Electron Beams with Energy up…
A complete calculation of the corrections to pion-deuteron scattering length up to order $\chi^{3/2}$ with $\chi=m_{\pi}/M_{N}$ is performed. The calculation includes the dispersive contributions and corrections due to the explicit…
Pion-nucleus scattering cross sections are calculated by solving a Schr\"{o}dinger equation reduced from the Klein-Gordon equation. Local potentials are assumed, and phenomenological potential parameters are searched energy-dependently for…
An energy-dependent and set of single-energy partial-wave analyses of $NN$ elastic scattering data have been completed. The fit to 1.6~GeV has been supplemented with a low-energy analysis to 400 MeV. Using the low-energy fit, we study the…
We use the framework of effective field theories to discuss the determination of the S-wave \pi N scattering lengths from the recent high-precision measurements of pionic deuterium observables. The theoretical analysis proceeds in several…
This work discusses the approximations frequently used to calculate the contribution to pion production in proton-proton scattering near threshold from irreducible pion re-scattering. The reference result is obtained from the quantum…
We derive a set of sum rules for threshold parameters of pion-pion scattering whose dispersion integrals are rapidly convergent and are dominated by S- and P-waves absorptive parts. Stringent constraints on some threshold parameters are…
An old calculation of the s-wave pi-pi scattering lengths is updated and supplemented with experimental data on the pi-pi s-wave phase shift. The results ma0 = .215 and ma2 = -.039 are in excellent agreement with those obtained from a…
Peculiarities of obtaining parameters for broad multi-channel resonances from data are discussed analyzing the experimental data on processes $\pi\pi\to\pi\pi,K\bar{K}$ in the $I^GJ^{PC}=0^+0^{++}$ channel in a model-independent approach…
Fully constrained bubble chamber data on the pp -> pi+ pn and pp -> pi+ d reactions are used to investigate the ratio of the counting rates for the two processes as function of the pn excitation energy Q. Though it is important to include…
A detailed investigation of the reaction np -> pp\pi^{-} has been carried out using the data obtained with the continuous neutron beam produced by charge exchange scattering of protons off a deuterium target. A partial wave event-by-event…
We consider the impact of two recent pi- p-->eta n measurements on the etaN scattering length and etaN branching fractions for the N(1535) and N(1520) resonances within a coupled-channel analysis of piN elastic scattering and etaN…
The quenched chiral logs are examined on a $16^3 \times 28$ lattice with Iwasaki gauge action and overlap fermions. The pion decay constant $f_{\pi}$ is used to set the lattice spacing, $a = 0.200(3) {\rm fm}$. With pion mass as low as…
The SciBooNE Collaboration has performed a search for charged current coherent pion production from muon neutrinos scattering on carbon, \nu_\mu ^{12}C \to \mu^- ^{12}C \pi^+, with two distinct data samples. No evidence for coherent pion…
Using unitarized Chiral Perturbation Theory methods, we perform a detailed analysis of the $\pi\pi$ scattering poles $f_0(600)$ and $\rho(770)$ behaviour when medium effects such as temperature or density drive the system towards Chiral…
We calculate the s-wave pion-pion scattering length in the isospin I=2 channel in lattice QCD for pion masses ranging from 270 Mev to 485 Mev using two flavors of maximally twisted mass fermions at a lattice spacing of 0.086 fm.…
The influence of the mass difference between the charged and neutral pions on the low-energy characteristics of nucleon-nucleon interaction in the $^{1}S_{0}$ spin-singlet state is studied within the framework of the effective-range…
The lifetime measurement of pi+pi- atoms (A2pi) with 10% precision provides in a model independent way the difference between the S-wave pion-pion scattering lengths for isospin 0 and 2, |a0 -a2|, with 5% accuracy. The scattering lengths a0…
The scattering lengths of the pi Sigma systems are key quantities in understanding the structure of the Lambda(1405) resonance and the subthreshold extrapolation of the barK N interaction. We demonstrate that the pi Sigma scattering lengths…