English

Dispersion Relation Constrained Partial Wave Analysis of piN Elastic and piN\to\etaN Scattering Data: The Baryon Spectrum

Nuclear Theory 2008-11-26 v2 High Energy Physics - Experiment High Energy Physics - Phenomenology Nuclear Experiment

Abstract

We present results from a comprehensive partial-wave analysis of pi+-p elastic scattering and charge-exchange data, covering the region from threshold to 2.1 GeV in the lab pion kinetic energy, employing a coupled-channel formalism to simultaneously fit pi-p\to\eta n data to 0.8 GeV. Our main result, solution FA02, utilizes a complete set of forward and fixed-t dispersion relation constraints, from threshold to 1 GeV, and from t = 0 to -0.4 (GeV/c)^2, applied to the piN elastic amplitude. A large number of systematic checks have been performed, including fits with no charge-exchange data and other database changes, fits with few or no dispersion relation constraints, and changes to the Coulomb correction scheme. We have also reexamined methods used to extract Breit-Wigner resonance parameters. The quality of fit to both data and dispersion relation constraints is superior to our earlier work. The results of these analyses are compared with previous solutions in terms of their resonance spectra and preferred values for couplings and low-energy parameters, including the piNN coupling constant.

Keywords

Cite

@article{arxiv.nucl-th/0311089,
  title  = {Dispersion Relation Constrained Partial Wave Analysis of piN Elastic and piN\to\etaN Scattering Data: The Baryon Spectrum},
  author = {R. A. Arndt and W. J. Briscoe and I. I. Strakovsky and R. L. Workman and M. M. Pavan},
  journal= {arXiv preprint arXiv:nucl-th/0311089},
  year   = {2008}
}

Comments

30 pages, including 12 tables and 15 figures. Changes made to the table of residues. Minor changes to the text. Qualitative results remain unchanged