Off-shell behavior of the pion-nucleon elastic amplitude

Journal Article · Sun Jul 15 04:00:00 EDT 1979 · AIP Conf. Proc.; (United States)

DOI:https://doi.org/10.1063/1.31969· OSTI ID:5884330

Ernst, D J

Simple models of the off-shell behavior of pion-nucleon amplitudes are reviewed. The separable potential model which includes the coupling of inelastic channels to elastic channels is derived. It is shown that the dominant, low-momentum behavior of the separable potential is determined by kinematic considerations. Recent results in the S, D, and F-wave channels of Ernst and Johnson are presented. It is argued that in P-wave channels, the presence of the nucleon pole in the amplitude requires a model that is similar to the Chew-Low model. The off-shell behavior of this amplitude is shown to differ from the separable potential model. Results of the model of Ernst and Johnson for P-wave amplitudes are presented. Off-shell effects in elastic pion-nucleon elastic scattering are examined. First, it is shown that different off-shell extrapolations are required for different choices of the basic propagator. Secondly, the dependence of elastic pion-nucleus scattering on the off-shell extrapolation and the choice of propagators is examined.

• Research Organization: Texas AM University, College Station, Texas 77843
• OSTI ID: 5884330
• Report Number(s): CONF-790347-
• Journal Information: AIP Conf. Proc.; (United States), Journal Name: AIP Conf. Proc.; (United States) Vol. 54:1; ISSN APCPC
• Country of Publication: United States
• Language: English

Related Subjects

645206* -- High Energy Physics-- Particle Interactions & Properties-Theoretical-- Strong Interactions
Baryon No. = 1-- (-1987)
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
AMPLITUDES
DIFFERENTIAL EQUATIONS
ELASTIC SCATTERING
EQUATIONS
HADRON-HADRON INTERACTIONS
INTERACTIONS
KLEIN-GORDON EQUATION
MATHEMATICAL MODELS
MATRICES
MESON-BARYON INTERACTIONS
MESON-NUCLEON INTERACTIONS
NUCLEAR MODELS
NUCLEAR POTENTIAL
P WAVES
PARTIAL WAVES
PARTICLE INTERACTIONS
PHASE SHIFT
PION-NUCLEON INTERACTIONS
POTENTIALS
PROPAGATOR
S MATRIX
SCATTERING
SCATTERING AMPLITUDES
SHELL MODELS
UNITARITY
WAVE EQUATIONS