Gauge invariance and the electromagnetic current of composite pions

Journal Article · Sat Jan 01 04:00:00 EST 1994 · Physical Review, C (Nuclear Physics); (United States)

DOI:https://doi.org/10.1103/PhysRevC.49.478· OSTI ID:5339795

Frank, M R ^[1]; Tandy, P C ^[2]

---

1. Department of Physics, Hampton University, Hampton, Virginia 23668 (United States) Continuous Electron Beam Accelerator Facility, 12000 Jefferson Avenue, Newport News, Virginia 23606 (United States)
2. Center for Nuclear Research, Department of Physics, Kent State University, Kent, Ohio 44242 (United States)

The Global Color-symmetry Model of QCD is extended to deal with a background electromagnetic field and the associated conserved current is identified for the finite size [ital [bar q]q] pion modes at tree level. We work within a well-defined truncation that factorizes the bilocal pion field into a local field variable and a hadronic form factor having a ladder Bethe-Salpeter content. The associated pion charge form factor is formulated. These developments are used to provide an illustration of how an effective hadronic action containing form factors may be electrmagnetically coupled in a gauge invariant way that is accountable to its field substructure. In particular, the Ward-Takahashi identity for the photon vertex appropriate to the localized pion fields is seen to contain the hadronic form factors. In this context, gauge invariance of the effective hadronic action also requires recognition of the fact that the free inverse propagator for the localized pion field gauge transforms due to the substructure field content that has been absorbed into it.

• OSTI ID: 5339795
• Journal Information: Physical Review, C (Nuclear Physics); (United States), Journal Name: Physical Review, C (Nuclear Physics); (United States) Vol. 49:1; ISSN 0556-2813; ISSN PRVCAN
• Country of Publication: United States
• Language: English

Related Subjects

662390 -- Electromagnetic Processes & Properties-- (1992-)
662420* -- Properties of Mesons & Meson Resonances-- (1992-)
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
BASIC INTERACTIONS
BETHE-SALPETER EQUATION
BOSONS
COLOR MODEL
COMPOSITE MODELS
CURRENTS
ELECTROMAGNETIC FIELDS
ELECTROMAGNETIC INTERACTIONS
ELECTRON-MESON INTERACTIONS
ELECTRON-PION INTERACTIONS
ELEMENTARY PARTICLES
EQUATIONS
FORM FACTORS
GAUGE INVARIANCE
HADRONS
INTERACTIONS
INVARIANCE PRINCIPLES
LEPTON-HADRON INTERACTIONS
LEPTON-MESON INTERACTIONS
MATHEMATICAL MODELS
MESONS
PARTICLE INTERACTIONS
PARTICLE MODELS
PARTICLE PROPERTIES
PIONS
PSEUDOSCALAR MESONS
QUARK MODEL