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First observation of in-medium effects on phase space distributions of antikaons measured in proton-nucleus collisions

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 نشر من قبل Frank Dohrmann
 تاريخ النشر 2005
  مجال البحث
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Differential production cross sections of $K^{pm}$ mesons have been measured in $p$ + C and $p$ + Au collisions at 1.6, 2.5 and 3.5 GeV proton beam energy. At beam energies close to the production threshold, the $K^-$ multiplicity is strongly enhanced with respect to proton-proton collisions. According to microscopic transport calculations, this enhancement is caused by two effects: the strangeness exchange reaction $NY to K^- NN$ and an attractive in-medium $K^-N$ potential at saturation density.



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