Vector resonances and electromagnetic nucleon structure
Motivated by new, precise magnetic proton form factor data in the timelike region, a hybrid vector meson dominance (hVMD) formalism is employed to investigate the significance of excited vector meson resonances on electromagnetic nucleon structure. We find that the rho (1700), omega (1600), and two previously unobserved states are required to reproduce the local structure seen in the new LEAR data just above the pp-bar threshold. We also investigate sensitivity to the phi meson. The model dependence of our result is tested by introducing an alternative model which couples the isoscalar vector meson states to a hypothetical vector glueball resonance. We obtain nearly identical results from both models, except for GnE(q2) in the spacelike region which is very sensitive to the glueball mass and the effective phi NN coupling.
- Research Organization:
- Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States)
- Sponsoring Organization:
- USDOE Office of Energy Research (ER) (US)
- DOE Contract Number:
- AC05-84ER40150
- OSTI ID:
- 828322
- Report Number(s):
- CEBAF-TH-95-22; DOE/ER/40150-2846; TRN: US0403923
- Journal Information:
- Physical Review, C (Nuclear Physics), Vol. 51, Issue 2; Other Information: PBD: 1 Feb 1995
- Country of Publication:
- United States
- Language:
- English
Similar Records
Elastic meson form factors with modified vector resonance propagators
Nucleon Strangeness Content through Vector Meson Dominance