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Observation of a cusp-like structure in the $gamma p rightarrow K^+Sigma^0$ cross section at forward angles and low momentum transfer

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 نشر من قبل Thomas Jude Dr
 تاريخ النشر 2020
  مجال البحث
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The $gamma p rightarrow K^+Sigma^0$ differential cross section at extremely forward angles was measured at the BGOOD experiment. A three-quarter drop in strength over a narrow range in energy and a strong dependence on the polar angle of the $K^+$ in the centre-of-mass of the reaction is observed at a centre-of-mass energy of 1900,MeV. Residing close to multiple open and hidden strangeness thresholds, the structure appears consistent with meson-baryon threshold effects which may contribute to the reaction mechanism.



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