{gamma}N{delta} form factors and Wigner rotations

Journal Article · Tue Sep 15 04:00:00 EDT 2009 · Physical Review. C, Nuclear Physics

DOI:https://doi.org/10.1103/PHYSREVC.80.038201· OSTI ID:21293895

Slaughter, Milton Dean ^[1]

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1. Department of Physics, Florida International University, Miami, Florida 33199 (United States)

For more than 50 years the {delta}{gamma} nucleon resonance isobar transition form factors G{sub M}*(q{sup 2}), G{sub E}*(q{sup 2}), and G{sub C}*(q{sup 2}) have been studied experimentally, theoretically, and phenomenologically. Although there has been substantial progress in understanding their behavior, there remains much work to be done. The {delta} resonance mass position and width remain ambiguous. A major tool used in many investigations is the Jones-Scadron {delta} rest frame parametrization of the three {delta}N{gamma} form factors. We point out that many studies utilizing this parametrization and related formulations and which utilize the {delta} rest frame (c.m. frame) may not account for Wigner rotations and the consequent helicity mixing that ensues when the {delta} is not at rest (lab frame) thus adversely affecting the accurate and precise determination of these form factors.

• OSTI ID: 21293895
• Journal Information: Physical Review. C, Nuclear Physics, Journal Name: Physical Review. C, Nuclear Physics Journal Issue: 3 Vol. 80; ISSN 0556-2813; ISSN PRVCAN
• Country of Publication: United States
• Language: English

Related Subjects

73 NUCLEAR PHYSICS AND RADIATION PHYSICS
FORM FACTORS
GAMMA RADIATION
HELICITY
MASS
MIXING
NUCLEONS
PHOTON-NUCLEON INTERACTIONS
RESONANCE