相关论文: Extraction of P11 Resonance from pi-N Data and Its…
We address a question about how much resonance poles and residues extracted from data depend on a model used for the extraction, and on the precision of data. We focus on the P11 pi-N scattering and use the dynamical coupled-channel (DCC)…
We study the stability of resonance poles in pi-N P_11 partial wave, particularly the Roper resonance, by varying parameters significantly within the EBAC dynamical coupled-channels model, keeping a good fit to the empirical amplitude. We…
We present the dynamical origin of the P11 nucleon resonances resulting from a dynamical coupled-channels (DCC) analysis of meson production reactions off a nucleon target, which is conducted at Excited Baryon Analysis Center (EBAC) of…
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 present organization and solutions for a new analysis of all $\pi N$ elastic and the major inelastic channels to extract detailed characteristics of the contributing baryon resonances. This work is based on the work of R. Cutkosky and…
We show that two almost degenerate poles near the $\pi\Delta$ threshold and the next higher mass pole in the $P_{11}$ partial wave of $\pi N$ scattering evolve from a single bare state through its coupling with $\pi N$, $\eta N$ and $\pi\pi…
Each and every energy dependent partial-wave analysis is parameterizing the pole positions in a procedure defined by the way how the continuous energy dependence is implemented. These pole positions are, henceforth, inherently model…
We present a pedagogical study of the commonly employed Speed-Plot (SP) and Time-delay (TD) methods for extracting the resonance parameters from the data of two particle coupled-channels reactions. Within several exactly solvable models, it…
The properties of baryon resonances are extracted from a complicated process of fitting sophisticated, empirical models to data. The reliability of this process comes from the quality of data and the robustness of the models employed. With…
We analyze Pion Nucleon Scattering up to 700 MeV using a simple, relativistic, unitary model\cite{1}. The kernel of the integral equation includes nucleon, roper, delta, D_13 as well as S_11 poles with their corresponding crossed pole terms…
We develop a robust method to extract the pole configuration of a given partial-wave amplitude. In our approach, a deep neural network is constructed where the statistical errors of the experimental data are taken into account. The teaching…
We present the results on P11 resonances obtained with Dubna-Mainz-Taipei (DMT) dynamical model for pion-nucleon scattering and pion electromagnetic production. The extracted values agree well, in general, with PDG values. One pole is found…
We explain how an analytic continuation we have developed recently is applied to determine the residues of the nucleon resonance poles within a dynamical coupled-channel model of meson-baron reactions. A procedure for evaluating the…
We explain the application of a recently developed analytic continuation method to extract the electromagnetic transition form factors for the nucleon resonances ($N^*$) within a dynamical coupled-channel model of meson-baryon…
We discuss the analysis of data from piN elastic scattering and single pion photo- and electroproduction. The main focus is a study of low-lying non-strange baryon resonances. Here we concentrate on some difficulties associated with…
We present the results of energy-dependent and single-energy partial-wave analyses of $\pi$N elastic scattering data with laboratory kinetic energies below 2.1~GeV. Resonance structures have been extracted using Breit-Wigner fits, speed…
The reactions $\gamma p\to\pi^0 p$ and $\gamma p\to\pi^+ n$ are analyzed in a semi-phenomenological approach up to $E\sim2.3$ GeV. Fits to differential cross section and single and double polarization observables are performed. A good…
A unitary multi-channel approach, first developed by the Carnegie-Mellon- Berkeley group, is applied to extract the pole positions, masses, and partial decay widths of nucleon resonances. Input used are the partial wave amplitudes for the…
We have investigated the model dependence of meson resonance properties extracted from the Dalitz-plot analysis of the three-pions photoproduction reactions on the nucleon. Within a unitary model developed in Phys. Rev. D 84, 114019 (2011),…
We present an alternative interpretation for the dynamical origin of the P11 nucleon resonances, which results from the dynamical coupled-channels analysis at Excited Baryon Analysis Center of Jefferson Lab. The results indicate the crucial…