2003/11/30 by R. A. Arndt, W. J. Briscoe, I. I. Strakovsky +2 · 4 citations
Physics and Astronomy · #High-Energy Particle Collisions Research #Particle physics theoretical and experimental studies #Quantum Chromodynamics and Particle Interactions #hep-ex #hep-ph #nucl-ex #nucl-th
paper · pdf · doi:10.1103/physrevc.69.035213
published as Phys.Rev.C69:035213,2004 · 30 pages, including 12 tables and 15 figures. Changes made to the table of residues. Minor changes to the text. Qualitative results remain unchanged
arxiv created 2004/01/23 · openalex publication_date 2004/03/31 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/28
We present results from a comprehensive partial-wave analysis of \ensuremathπ^\ifmmode±\else\textpm\fip elastic scattering and charge-exchange data, covering the region from threshold to 2.1\phantom\rule0.3em0exGeV in the lab pion kinetic energy, employing a coupled-channel formalism to simultaneously fit \ensuremathπ^\ensuremath-p\ensuremath→\ensuremathηn data to 0.8\phantom\rule0.3em0exGeV. Our main result, solution FA02, utilizes a complete set of forward and fixed-t dispersion relation constraints, from threshold to 1\phantom\rule0.3em0exGeV, and from t=0 to \ensuremath-0.4\phantom\rule0.3em0ex(GeV∕c)2, applied to the \ensuremathπN 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 \ensuremathπNN coupling constant.