Theory of the low-energy pion-nucleon interaction

Journal Article · Wed Mar 01 04:00:00 EST 1978 · Phys. Rev., C; (United States)

DOI:https://doi.org/10.1103/PhysRevC.17.1125· OSTI ID:6776449

Banerjee, M K; Cammarata, J B

A once-subtracted form of the Low equation for the pion-nucleon scattering amplitude is derived, with partial conservation of axial-vector current used to define the amplitude when one pion is off the mass shell. The static approximation is not made and both the seagull terms and the antinucleon contribution (z graphs) are retained. The theory is applied to calculate the S-wave amplitudes in the elastic scattering region. Good agreement is found with the phase shift fits to the data when we use vertical-barg/sub ..pi../(4M/sup 2/) vertical-bar = 11.69 and 25.5 MeV for the ..pi..N sigma commutator. The implications of this work for the analysis of low-energy elastic scattering of pions form nuclei are discussed. In particular, we point out how this work establishes the presence of a Laplacian term in the pion-nucleus optical potential with a magnitude that is fixed from the value of the sigma commutator.

• Research Organization: Department of Physics and Astronomy, University of Maryland, College Park, Maryland 20742
• OSTI ID: 6776449
• Journal Information: Phys. Rev., C; (United States), Journal Name: Phys. Rev., C; (United States) Vol. 17:3; ISSN PRVCA
• Country of Publication: United States
• Language: English

Related Subjects

653003* -- Nuclear Theory-- Nuclear Reactions & Scattering
73 NUCLEAR PHYSICS AND RADIATION PHYSICS
AMPLITUDES
ELASTIC SCATTERING
EQUATIONS
HADRON-HADRON INTERACTIONS
INTERACTIONS
INVARIANCE PRINCIPLES
LORENTZ INVARIANCE
LOW EQUATION
MATHEMATICAL MODELS
MESON-BARYON INTERACTIONS
MESON-NUCLEON INTERACTIONS
NUCLEAR MODELS
OPTICAL MODELS
PARTIAL WAVES
PARTICLE INTERACTIONS
PCAC THEORY
PHASE SHIFT
PION-NUCLEON INTERACTIONS
S WAVES
SCATTERING
SCATTERING AMPLITUDES
SHELL MODELS