Related papers: Precise determination of resonance pole parameters…
Lattice QCD results for isospin $I=\frac{1}{2}$ $D\pi$ scattering are presented. Utilizing a series of $N_{\text{f}}=2+1$ Wilson-Clover ensembles with pion masses of $m_\pi \approx 132, 208, 305$ and $317$ MeV, various two-particle…
We formulate and demonstrate experimentally the high-resolution spectral method based on Bloch-wave symmetry properties for extracting mode dispersion in periodic waveguides from measurements of near-field profiles. We characterize both the…
A simple heuristic argument to understand the existence of complex branch points in the $\pi N$ scattering amplitude is presented. It is based on a hypothesis that the singularity structure of the $\pi N$ scattering amplitude is a smooth…
We complete and improve the fits to experimental $\pi\pi$ scattering amplitudes, both at low and high energies, that we performed in the previous papers of this series. We then verify that the corresponding amplitudes satisfy analyticity…
We show that two P11 nucleon resonance poles near the pi Delta threshold, obtained in several analyses, are stable against large variations of parameters within a dynamical coupled-channels analysis based on meson-exchange mechanisms. By…
We calculate the pion-pion elastic scattering phase shifts for pion masses from the chiral limit to values of interest for lattice studies. At low energies, we use the standard Chiral Perturbation Theory expressions to one and two loops. In…
We present a determination of the isovector, $P$-wave $\pi\pi$ scattering phase shift obtained by extrapolating recent lattice QCD results from the Hadron Spectrum Collaboration using $m_\pi =236$ MeV. The finite volume spectra are…
We extract K-matrix poles from our fits to elastic pion-nucleon scattering and eta-nucleon production data in order to test a recently proposed method for the determination of resonance properties, based on the trace of the K-matrix. We…
We study isospin-1 P-wave $\pi\pi$ scattering in lattice QCD with two flavours of O($a$) improved Wilson fermions. For pion masses ranging from $m_\pi=265$ MeV to $m_\pi=437$ MeV, we determine the energy spectrum in the centre-of-mass frame…
We conduct a two-flavor ($N_f=2$) lattice QCD calculation of the elastic phase-shifts for pion-pion scattering in the scalar, isoscalar channel (the $\sigma$-meson). The calculation is performed for two quark masses corresponding to a pion…
We present the first direct determination of meson-baryon resonance parameters from a scattering amplitude calculated using lattice QCD. In particular, we calculate the elastic $I=3/2$, $p$-wave nucleon-pion amplitude on a single ensemble…
We present a pedagogical study of the commonly employed Speed-Plot (SP) and Time-delay (TD) methods for extracting the resonance parameters from the data of two particle coupled-channels reactions. Within several exactly solvable models, it…
By separating data points close to a resonance into intervals, and fitting all possible intervals to a simple pole with constant coherently added background, we obtained a substantial number of convergent fits. After a carefully chosen set…
With the aim of extracting the pion charge radius, we analyse extant precise pion+electron elastic scattering data on $Q^2 \in [0.015,0.144]\,$GeV$^2$ using a method based on interpolation via continued fractions augmented by statistical…
We revisit the information on the two lightest $a_0$ resonances and $S$-wave $\pi\eta$ scattering that can be extracted from photon-photon scattering experiments. For this purpose we construct a model for the $S$-wave photon-photon…
Radial phase shifts ($\delta(r)$), amplitude functions ($A(r)$), and exact wavefunctions ($u(r)$) for various uncoupled S, P, and D channels of neutron--proton scattering have been calculated using the Phase Function Method (PFM). In these…
We propose parameterization procedures of the scattering amplitude f_{1+}^{3}(s)) with a view to extracting the pole parameters from data in the elastic region of {\pi}N scattering. This is achieved by considering the analyticity properties…
A new partial wave analysis of pion photoproduction has been obtained in the framework of fixed-t dispersion relations valid form threshold up to 500 MeV. It is based on new Mainz data for \pi^{0} and \pi^{+} production off the proton and…
We calculate the parameters describing elastic $I=1$, $P$-wave $\pi\pi$ scattering using lattice QCD with $2+1$ flavors of clover fermions. Our calculation is performed with a pion mass of $m_\pi \approx 320\:\:{\rm MeV}$ and a lattice size…
We provide global parameterizations of $\pi\pi$ scattering $S0$ and $P$ partial waves up to roughly 2 GeV for phenomenological use. These parameterizations describe the output and uncertainties of previous partial-wave dispersive analyses…