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J/psi production at high transverse momentum in p+p and Cu+Cu collisions at sNN=200GeV

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 نشر من قبل Zebo Tang
 تاريخ النشر 2009
  مجال البحث
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The STAR collaboration at RHIC presents measurements of Jpsi$to{e^+e^-}$ at mid-rapidity and high transverse momentum ($p_T>5$ GeV/$c$) in pp and central cucu collisions at sNN = 200 GeV. The inclusive Jpsi production cross section for cucu collisions is found to be consistent at high $p_T$ with the binary collision-scaled cross section for pp collisions, in contrast to previous measurements at lower $p_T$, where a suppression of Jpsi production is observed relative to the expectation from binary scaling. Azimuthal correlations of $J/psi$ with charged hadrons in pp collisions provide an estimate of the contribution of $B$-meson decays to Jpsi production of $13% pm 5%$.



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