Unitary theory of pion photoproduction in the chiral bag model

Journal Article · Wed Jul 01 04:00:00 EDT 1987 · Phys. Rev. C; (United States)

DOI:https://doi.org/10.1103/PhysRevC.36.250· OSTI ID:6493544

Araki, M; Afnan, I R

We present a multichannel unitary theory of single pion photoproduction from a baryon B. Here, B is the nucleon or ..delta..(1232), with possible extension to include the Roper resonance and strange baryons. We treat the baryon as a three-quark state within the framework of the gauge and chiral Lagrangian, derived from the Lagrangian for the chiral bag model. By first exposing two-body, and then three-body unitarity, taking into consideration the ..pi pi..B and ..gamma pi..B intermediate states, we derive a set of equations for the amplitudes both on and off the energy shell. The Born term in the expansion of the amplitude has the new feature that the vertices in the pole diagram are undressed, while those in the crossed, contact, and pion pole diagrams are dressed.

• Research Organization: School of Physical Sciences, The Flinders University of South Australia, Bedford Park, South Australia 5042, Australia
• OSTI ID: 6493544
• Journal Information: Phys. Rev. C; (United States), Journal Name: Phys. Rev. C; (United States) Vol. 36:1; ISSN PRVCA
• Country of Publication: United States
• Language: English

Related Subjects

645203* -- High Energy Physics-- Particle Interactions & Properties-Theoretical-- Weak Interactions & Properties
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
BAG MODEL
BARYONS
BASIC INTERACTIONS
BOSONS
CHARGED-PARTICLE REACTIONS
CHIRAL SYMMETRY
COMPOSITE MODELS
COUPLING CONSTANTS
DELTA-1236 RESONANCES
ELECTROMAGNETIC INTERACTIONS
ELEMENTARY PARTICLES
EXTENDED PARTICLE MODEL
FERMIONS
FIELD THEORIES
FUNCTIONS
GAUGE INVARIANCE
HADRON REACTIONS
HADRONS
INTERACTIONS
INVARIANCE PRINCIPLES
LAGRANGIAN FUNCTION
MANY-BODY PROBLEM
MATHEMATICAL MODELS
MESON REACTIONS
MESONS
NUCLEAR REACTIONS
NUCLEONS
PARTICLE INTERACTIONS
PARTICLE MODELS
PARTICLE PRODUCTION
PHOTON-BARYON INTERACTIONS
PHOTON-HADRON INTERACTIONS
PHOTON-NUCLEON INTERACTIONS
PHOTONUCLEAR REACTIONS
PHOTOPRODUCTION
PION REACTIONS
PIONS
POSTULATED PARTICLES
PROPAGATOR
PSEUDOSCALAR MESONS
QUANTUM CHROMODYNAMICS
QUANTUM FIELD THEORY
QUARK MODEL
QUARKS
RENORMALIZATION
S CHANNEL
STRANGE PARTICLES
SYMMETRY
THREE-BODY PROBLEM
TWO-BODY PROBLEM
UNITARY POLE APPROXIMATION