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Near-threshold Photoproduction of Phi Mesons from Deuterium

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 نشر من قبل Xin Qian
 تاريخ النشر 2010
  مجال البحث
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We report the first measurement of the differential cross section on $phi$-meson photoproduction from deuterium near the production threshold for a proton using the CLAS detector and a tagged-photon beam in Hall B at Jefferson Lab. The measurement was carried out by a triple coincidence detection of a proton, $K^+$ and $K^-$ near the theoretical production threshold of 1.57 GeV. The extracted differential cross sections $frac{dsigma}{dt}$ for the initial photon energy from 1.65-1.75 GeV are consistent with predictions based on a quasifree mechanism. This experiment establishes a baseline for a future experimental search for an exotic $phi$-N bound state from heavier nuclear targets utilizing subthreshold/near-threshold production of $phi$ mesons.

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