Deep inelastic Scattering , QCD , and generalised vector dominance
نویسندگان
چکیده
We provide a formulation of generalised vector dominance (GVD) for low– x deep-inelastic scattering that explicitly incorporates the γ * → q ¯ q transition and a QCD-inspired ansatz for the (q ¯ q)p forward-scattering amplitude. The destructive interference originally introduced in off-diagonal GVD is recovered in the present formulation and traced back to the generic structure of two-gluon-exchange as incorporated into the notion of colour transparency. Asymptotically, the transverse photoabsorption cross section behaves as (ln Q 2)/Q 2 , implying a logarithmic violation of scaling for F 2 , while the longitudinal-to-transverse ratio decreases as 1/ ln Q 2 .
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