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Leakage Effect on J/psi Pt Distributions in Different Centrality Bins for Pb-Pb Collisions at E/A=160 GeV

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 نشر من قبل Xianglei Zhu
 تاريخ النشر 2003
  مجال البحث
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A transport approach including a leakage effect for J/psis in the transverse phase space is used to calculate the ratios between the J/psi transverse momentum distributions in several centrality bins for Pb-Pb collisions at E/A = 160 GeV. From the comparison with the CERN-SPS data, where the centrality is characterized by the transverse energy Et, the leakage effect is extremely important in the region of high transverse momentum and high transverse energy, and both the threshold and the comover models can describe the ratio well for all centrality bins except the most central one (Et < 100 GeV), for which the comover model calculation is considerably better than the threshold one.

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