Gauge-Invariant Scaling Model of Current Interactions with Regge Behavior and Finite Fixed-Pole Sum Rules

Journal Article · 15 November 1973 · Physical Review. D, Particles Fields

DOI: https://doi.org/10.1103/PhysRevD.8.3678 · OSTI ID:1442850

Brodsky, Stanley J. ^[1]; Close, Francis E. ^[2]; Gunion, J. F. ^[3]

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1. Stanford Univ., Stanford, CA (United States)
2. Stanford Univ., Stanford, CA (United States); Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States)
3. Stanford Univ., Stanford, CA (United States); Daresbury Nuclear Physics Lab. (England)

A general nonperturbative model for the entire Compton amplitude which incorporates Bjorken scaling, gauge invariance, and Regge behavior is presented. We show that a covariantly regularized model based on the infinite-momentum-frame techniques of Drell, Levy, and Yan is equivalent to the manifestly covariant nonperturbative parton model of Landshoff, Polkinghorne, and Short. We also demonstrate that a general consequence of composite theories of hadrons with field-theoretic constituents which incorporates the above properties is the existence of a constant energy-independent and q²-independent term in T₁(ν, q²) (a "Kronecker delta" δ_J0 term) and a J = 0 fixed pole in T₂(ν, q²). Sum rules for general Compton amplitudes are derived and a discussion of mass renormalization for electromagnetic self-energy corrections of hadrons is presented. We demonstrate that such sum rules are always finite, even in the presence of Regge behavior, when subtraction terms in the underlying parton-proton u-channel dispersion relation are taken into account. Here, analytic continuation in α is thus justified.

• Research Organization: SLAC National Accelerator Laboratory (SLAC), Menlo Park, CA (United States)
• Sponsoring Organization: USDOE Office of Science (SC)
• Grant/Contract Number: AC02-76SF00515
• OSTI ID: 1442850
• Report Number(s): SLAC-PUB--1243
• Journal Information: Physical Review. D, Particles Fields, Journal Name: Physical Review. D, Particles Fields Journal Issue: 10 Vol. 8; ISSN PRVDAQ; ISSN 0556-2821
• Publisher: American Physical Society (APS)Copyright Statement
• Country of Publication: United States
• Language: English