Spectral Content of Isoscalar Nucleon Form Factors
نویسندگان
چکیده
The nucleon strange vector and isoscalar electromagnetic form factors are studied using a spectral decomposition. The KK̄ contribution to the electric and magnetic radii as well as the magnetic moment is evaluated to all orders in the strong interaction using an analytic continuation of experimental KN scattering amplitudes and bounds from unitarity. The relationship between non-resonant and resonant KK̄ contributions to the form factors is demonstrated, and values for the vector and tensor φNN̄ couplings are derived. The KK̄ spectral functions are used to evaluate the credibility of model calculations for the strange quark vector current form factors. PACS: 14.20.Dh, 11.55.Fv, 12.38.Lg, 14.65.Bt
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