Generalized polarizabilities of the proton in a constituent quarkmodel
نویسندگان
چکیده
We study low-energy virtual Compton scattering oo the proton within the framework of a nonrelativistic constituent quark model. The Compton ten-sor is divided into two separately gauge-invariant contributions. The rst consists of the groundstate propagation in the direct and crossed channels together with an appropriately chosen term to satisfy gauge invariance. The residual part contains the relevant structure information characterized by the so-called generalized polarizabilities. We discuss two diierent schemes to obtain the generalized polarizabilities from the residual term. Explicit predictions for the generalized polarizabilities are presented for the Isgur-Karl model. Our results are compared with previous predictions in that model as well as other approaches.
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Generalized polarizabilities of the proton in a constituent quark model revisited
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