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Pseudovector versus pseudoscalar coupling in kaon photoproduction - revisited

S. S. Hsiao·D. H. Lu·Shin Nan Yang
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Abstract

The question of pseudovector versus pseudoscalar coupling schemes for the kaon-hyperon-nucleon interaction is re-examined for the reaction $γp\to K^+ Λ$ in several isobaric models. These models typically include Born terms, $K^*$- and $K_1$-exchange in the t-channel, and a few different combinations of spin-1/2 baryon resonances in the $s$- and $u$-channels. The coupling constants are obtained by fitting to a large data set. We find that both pseudoscalar and pseudovector couplings can allow for a satisfactory description of the present database. The resulting coupling constants, $g_{KΛN}$ and $g_{KΣN}$, in the pseudovector coupling scheme are smaller than those predicted using flavor SU(3) symmetry, but consistent with the values obtained in a QCD sum rule calculation.

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S. S. Hsiao, D. H. Lu, Shin Nan Yang. 2000-04-05. Pseudovector versus pseudoscalar coupling in kaon photoproduction - revisited. https://doi.org/10.1103/physrevc.61.068201

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