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Comparing phenomenological recipes with a microscopic model for the electric amplitude in strangeness photoproduction

A. Yu. Korchin·O. Scholten
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Abstract

Corrections to the Born approximation in photo-induced strangeness production off a proton are calculated in a semi-realistic microscopic model. The vertex corrections and internal contributions to the amplitude of the $γp \to K^+ Λ$ reaction are included on the one-loop level. Different gauge-invariant phenomenological prescriptions for the modification of the Born contribution via the introduction of form factors and contact terms are discussed. In particular, it is shown that the popular minimal-substitution method of Ohta corresponds to a special limit of the more realistic approach.

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A. Yu. Korchin, O. Scholten. 2003-11-27. Comparing phenomenological recipes with a microscopic model for the electric amplitude in strangeness photoproduction. https://doi.org/10.1103/physrevc.68.045206

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