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Coherent Theta^+ and Lambda(1520) photoproduction off the deuteron

A. I. Titov·B. Kampfer·S. Daté·Y. Ohashi
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Abstract

We analyze an effect of the coherent $Θ^+Λ(1520)$ photoproduction in $γD$ interaction near the threshold. We demonstrate that the coherence effect becomes manifest in a comparison of the $nK^+$ invariant mass distribution when the $pK^-$ invariant equals the $Λ(1520)$ mass. Our model calculations indicate a sizeable contribution of resonant and non-resonant background processes in the $γD\to np K^+K^-$ reaction which generally exceed the contribution of the coherent resonant channel. However, we find that the coherent $Θ^+Λ(1520)$ photoproduction is enhanced relative to the background processes in the forward hemisphere of the $pK^-$ pair photoproduction. Moreover, the coherence effect does not depend on the $Θ^+$ photoproduction amplitude and is defined by the probabilities of the $Λ(1520)$ photoproduction and the $Θ^+\to NK$ transition. Therefore, this coherence effect may be used as an independent method for studying the mechanism of $Θ^+$ production and $Θ^+$ properties.

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A. I. Titov, B. Kampfer, S. Daté, Y. Ohashi. 2005-06-23. Coherent Theta^+ and Lambda(1520) photoproduction off the deuteron. https://doi.org/10.1103/physrevc.72.035206%2010.1103%2Fphysrevc.72.049901

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