Unitary meson-exchange calculation of NN. -->. NN. pi. reaction

Journal Article · Fri Oct 31 23:00:00 EST 1986 · Phys. Rev. C; (United States)

DOI:https://doi.org/10.1103/PhysRevC.34.1900· OSTI ID:6982754

Matsuyama, A; Lee, T H

Within a unitary ..pi..NN theory a set of coupled integral equations have been developed for the study of pion production from NN collisions, and have been applied to calculate the coincidence cross sections of pp..-->..pn..pi../sup +/ at 800 MeV. The calculation is based on a meson-exchange Hamiltonian which was previously constructed to describe NN elastic scattering up to 1 GeV by extending the Paris potential to include ..delta.. excitation. It involves solving a Faddeev-Alt-Grassberger-Sandhas scattering equation for the final ..pi..NN state and a NNdirect-sumN..delta.. coupled-channel equation for the initial NN state. We present the procedure of using the newly developed spline function method to solve the considered Faddeev-Alt-Grassberger-Sandhas equation directly on the real momentum axis. The importance of using a unitary approach to treat the initial NN and final ..pi..NN scattering is analyzed in detail, in order to understand the results obtained in several previous approaches by Betz, Dubach et al., and Verwest. The calculated cross sections reproduce the main features of the data both in magnitude and shape. The main difficulty of the present theory is found to be in reproducing the polarization data A/sub y/. Our results provide further evidence that the ..pi..NN dynamics cannot be described completely by the conventional meson-exchange model.

• Research Organization: Swiss Institute for Nuclear Research, Villigen, Switzerland and TRIUMF, Vancouver, British Columbia, Canada V6T 2A3
• OSTI ID: 6982754
• Journal Information: Phys. Rev. C; (United States), Journal Name: Phys. Rev. C; (United States) Vol. 34:5; ISSN PRVCA
• Country of Publication: United States
• Language: English

Related Subjects

645204* -- High Energy Physics-- Particle Interactions & Properties-Theoretical-- Strong Interactions & Properties
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
BARYON-BARYON INTERACTIONS
BOSON-EXCHANGE MODELS
BOSONS
COUPLED CHANNEL THEORY
DIAGRAMS
ELASTIC SCATTERING
ELEMENTARY PARTICLES
ENERGY RANGE
EQUATIONS
FADDEEV EQUATIONS
FEYNMAN DIAGRAM
FUNCTIONS
HADRON-HADRON INTERACTIONS
HADRONS
HAMILTONIANS
INTEGRAL EQUATIONS
INTERACTIONS
MATHEMATICAL MODELS
MATHEMATICAL OPERATORS
MESONS
MEV RANGE
MEV RANGE 100-1000
NUCLEON-NUCLEON INTERACTIONS
OBE MODEL
PARTICLE INTERACTIONS
PARTICLE MODELS
PARTICLE PRODUCTION
PERIPHERAL MODELS
PIONS
PIONS PLUS
PROTON-NUCLEON INTERACTIONS
PROTON-PROTON INTERACTIONS
PSEUDOSCALAR MESONS
QUANTUM OPERATORS
SCATTERING
SPLINE FUNCTIONS