Role of correlated two-pion exchange in [pi][ital N] scattering

Journal Article · Sun May 01 04:00:00 EDT 1994 · Physical Review, C (Nuclear Physics); (United States)

DOI:https://doi.org/10.1103/PhysRevC.49.2671· OSTI ID:5073751

Schuetz, C; Durso, J W; Holinde, K; Speth, J ^[1]

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1. Institut fuer Kernphysik, Forschungszentrum Juelich GmbH, D-52425 Juelich (Germany)

A model for the meson exchange in the scalar ([sigma]) and vector ([rho]) channel in the [pi][ital N] interaction based on correlated 2[pi] exchange is presented, which is obtained by using quasiempirical information about the [ital N[bar N]][r arrow]2[pi] amplitudes. Due to chiral symmetry constraints it turns out that [sigma] exchange is repulsive in [ital S] waves but attractive in [ital P] waves. The specific feature seems to be favored by the [pi][ital N] data. Concerning [rho] exchange our result is roughly twice as large as used in former more phenomenological treatments. Our model is supplemented by conventional (direct and exchange) pole diagrams involving a (bare) nucleon and [Delta] isobar, and is then unitarized by means of the relativistic Schroedinger equation, giving the [Delta] isobar a width determined by the dynamics of the model. Resulting [pi][ital N] phase shifts in the elastic region agree well with empirical information, as do scattering lengths and the [pi][ital N] [Sigma] term.

• OSTI ID: 5073751
• Journal Information: Physical Review, C (Nuclear Physics); (United States), Journal Name: Physical Review, C (Nuclear Physics); (United States) Vol. 49:5; ISSN 0556-2813; ISSN PRVCAN
• Country of Publication: United States
• Language: English

Related Subjects

662120 -- General Theory of Particles & Fields-- Symmetry
Conservation Laws
Currents & Their Properties-- (1992-)
662340 -- Hadron Interactions-- (1992-)
663110* -- General & Average Properties of Nuclei & Nuclear Energy Levels-- (1992-)
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
73 NUCLEAR PHYSICS AND RADIATION PHYSICS
BOSON-EXCHANGE MODELS
CHIRAL SYMMETRY
DATA
DIFFERENTIAL EQUATIONS
DIMENSIONS
ELASTIC SCATTERING
EQUATIONS
HADRON-HADRON INTERACTIONS
INFORMATION
INTERACTIONS
LENGTH
MATHEMATICAL MODELS
MESON-BARYON INTERACTIONS
MESON-NUCLEON INTERACTIONS
NUMERICAL DATA
PARTIAL DIFFERENTIAL EQUATIONS
PARTICLE INTERACTIONS
PARTICLE MODELS
PERIPHERAL MODELS
PHASE SHIFT
PION-NUCLEON INTERACTIONS
SCALAR FIELDS
SCATTERING
SCATTERING LENGTHS
SCHROEDINGER EQUATION
SIGMA MODEL
SYMMETRY
THEORETICAL DATA
VECTOR FIELDS
WAVE EQUATIONS