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Backward-angle photoproduction of $omega$ and $eta$ mesons from protons at $E_{gamma}=1.5-3.0$ GeV

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 نشر من قبل Yuhei Morino
 تاريخ النشر 2013
  مجال البحث
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We report the measurement of differential cross sections for $omega$ and $eta$ photoproduction from protons at backward angles ($-1.0<cosTheta_{C.M}^{X}<-0.8$) using linearly polarized photons at $E_{gamma}=$$1.5-3.0$ GeV. Differential cross sections for $omega$ mesons are larger than the predicted $u$-channel contribution in the energy range $2.0leqsqrt{s}leq2.4$ GeV. The differential cross sections for $omega$ and $eta$ mesons become closer to the predicted $u$-channel contribution at $sqrt{s}>2.4$ GeV. A bump structure in the $sqrt{s}$ dependence of the differential cross sections for $eta$ mesons was observed at $sqrt{s}sim$2.35 GeV.



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