High-Energy Photoproduction of Pseudoscalar Mesons in a Quark Model

Abstract

In the crossed $t$ channel the high-energy photoproduction of pseudoscalar mesons in photon-nucleon collisions is investigated in our $\mathrm{SU}\left(3\right)\mathrm{}$ quark model. Taking the physical baryon octet as $8\left(\mathrm{physical}\right)=8^{\prime }cos\theta +8\mathrm{}sin\theta$, where 8 and 8′ arise from $3\otimes \overline{3}$ and 3 ⊗ 6, respectively, we find that the value $\theta =20\mathrm{}°$, which explains the high-energy data on meson-baryon scattering, also explains the recent high-energy data on the photoproduction of pseudoscalar mesons. In particular, we find that for $\theta =20\mathrm{}°$, (i) $\frac{R\left(K^{+}\Lambda \right)}{R\left(K^{+}{\Sigma }^0\right)}=1.5\mathrm{}$, and (ii) the value of the strange-quark-to-nonstrange-quark coupling parameter is $b=0.4\mathrm{}\pm 0.04$.