Measurements of the electric and magnetic form factors of the proton from [ital Q][sup 2]=1. 75 to 8. 83 (GeV/[ital c])[sup 2]

Journal Article · Mon Oct 31 23:00:00 EST 1994 · Physical Review, D (Particles Fields); (United States)

DOI:https://doi.org/10.1103/PhysRevD.50.5491· OSTI ID:7170289

Andivahis, L; Bosted, P E; Lung, A; Stuart, L M; Alster, J; Arnold, R G; Chang, C C; Dietrich, F S; Dodge, W; Gearhart, R; Gomez, J; Griffioen, K A; Hicks, R S; Hyde-Wright, C E; Keppel, C; Kuhn, S E; Lichtenstadt, J; Miskimen, R A; Peterson, G A; Petratos, G G ; Rock, S E; Rokni, S; Sakumoto, W K; Spengos, M; Swartz, K; Szalata, Z; Tao, L H ^[1]

---

1. The American University; Washington; D.C. 20016 (United States) University of California; Davis; California 95616 (United States) Continuous Electron Beam Accelerator Facility; Newport News; Virginia 23606 (United States) Lawrence Livermore National Laboratory; Livermore; California 94550 (United States) University of Maryland; College Park; Maryland 20742 (United States) University of Massachusetts; Amherst; Massachusetts 01003 (United States) National Institute of Standards and Technology; Gaithersburg; Maryland 20899 (United States) University of Pennsylvania; Philadelphia; Pennsylvania 19104 (United States) Universit

The proton elastic form factors [ital G][sub [ital E][ital p]]([ital Q][sup 2]) and [ital G][sub [ital M][ital p]]([ital Q][sup 2]) have been extracted for [ital Q][sup 2]=1.75 to 8.83 (GeV/[ital c])[sup 2] via a Rosenbluth separation to [ital ep] elastic cross section measurements in the angular range 13[degree][le][theta][le]90[degree]. The [ital Q][sup 2] range covered more than doubles that of the existing data. For [ital Q][sup 2][lt]4 (GeV/[ital c])[sup 2], where the data overlap with previous measurements, the total uncertainties have been reduced to [lt] 14% in [ital G][sub [ital E][ital p]] and [lt] 1.5% in [ital G][sub [ital M][ital p]]. Results for [ital G][sub [ital E][ital p]]([ital Q][sup 2]) are consistent with the dipole fit [ital G][sub [ital D]]([ital Q][sup 2])=(1+[ital Q][sup 2]/0.71)[sup [minus]2], while those for [ital G][sub [ital M][ital p]]([ital Q][sup 2])/[mu][sub [ital p]][ital G][sub [ital D]]([ital Q][sup 2]) decrease smoothly from 1.05 to 0.92. Deviations from form factor scaling are observed up to 20%. The ratio [ital Q][sup 2][ital F][sub 2]/[ital F][sub 1] is observed to approach a constant value for [ital Q][sup 2][gt]3 (GeV/[ital c])[sup 2]. Comparisons are made to vector meson dominance, dimensional scaling, QCD sum rule, diquark, and constituent quark models, none of which fully characterize all the new data.

• DOE Contract Number: AC03-76SF00515
• OSTI ID: 7170289
• Journal Information: Physical Review, D (Particles Fields); (United States), Journal Name: Physical Review, D (Particles Fields); (United States) Vol. 50:9; ISSN PRVDAQ; ISSN 0556-2821
• Country of Publication: United States
• Language: English

Related Subjects

662230 -- Quantum Chromodynamics-- (1992-)
662330 -- Photon & Charged-Lepton Interactions with Hadrons-- (1992)
662390* -- Electromagnetic Processes & Properties-- (1992-)
662410 -- Properties of Baryons & Baryon Resonances-- (1992-)
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
BARYONS
COMPOSITE MODELS
CROSS SECTIONS
ELASTIC SCATTERING
ELECTROMAGNETIC FORM FACTORS
ELECTRON-NUCLEON INTERACTIONS
ELECTRON-PROTON INTERACTIONS
ELEMENTARY PARTICLES
EQUATIONS
FERMIONS
FIELD THEORIES
FORM FACTORS
HADRONS
INTERACTIONS
LEPTON-BARYON INTERACTIONS
LEPTON-HADRON INTERACTIONS
LEPTON-NUCLEON INTERACTIONS
MATHEMATICAL MODELS
MOMENTUM TRANSFER
NUCLEONS
PARTICLE INTERACTIONS
PARTICLE MODELS
PARTICLE PROPERTIES
PROTONS
QUANTUM CHROMODYNAMICS
QUANTUM FIELD THEORY
QUARK MODEL
SCALING
SCATTERING
SUM RULES
VECTOR DOMINANCE MODEL