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Off-shell effects in the electromagnetic production of strangeness

T. Mizutani·C. Fayard·G. -H. Lamot·B. Saghai
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Abstract

Previous approaches to the photo- and electro-production of strangeness off the proton, based upon effective hadronic Lagrangians, are extended here to incorporate the so called off-shell effects inherent to the fermions with spin >= 3/2. A formalism for intermediate-state, spin 3/2, nucleonic and hyperonic resonances is presented and applied to the processes $γ+ p ---> K^{+} + Λ$, for $E_γ^{lab}$ <= 2.5 GeV, $e + p ---> e' + K^+ + Λ$, as well as the branching ratio for the crossed channel reaction $K^- + p ---> γ+ Λ$, with stopped kaons. The sensitivity, from moderate to significant, of various observables to such effects are discussed.

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T. Mizutani, C. Fayard, G. -H. Lamot, B. Saghai. 1997-12-10. Off-shell effects in the electromagnetic production of strangeness. https://doi.org/10.1103/physrevc.58.75

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