Electromagnetic nucleon form-factors and their spectral functions in soliton models
Jun, 199623 pages
Published in:
- Z.Phys.A 356 (1996) 339-350
e-Print:
- hep-ph/9606336 [hep-ph]
Report number:
- SI-TH-96-3
Citations per year
Abstract:
It is demonstrated that in simple soliton models essential features of the electro-magnetic nucleon form factors observed over three orders of magnitude in momentum transfer are naturally reproduced. The analysis shows that three basic ingredients are required: an extended object, partial coupling to vector mesons, and relativistic recoil corrections. We use for the extended object the standard skyrmion, one vector meson propagator for both isospin channels, and the relativistic boost to the Breit frame. Continuation to timelike leads to quite stable results for the spectral functions in the regime from the 2- or 3-pion threshold to about two rho masses. Especially the onset of the continuous part of the spectral functions at threshold can be reliably determined and there are strong analogies to the results imposed on dispersion theoretic approaches by the unitarity constraint.Note:
- 24 pages, (RevTeX), 5 PS-figures; Data points in fig.2 and corresponding references added. Final version, to be published in Z.Physik A
- nucleon: form factor
- form factor: nucleon
- relativistic
- momentum transfer
- model: soliton
- spectral representation
- Skyrme model: nonrelativistic
- coupling: (nucleon vector meson)
- (nucleon vector meson): coupling
- recoil: correction
References(38)
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