اشترك بالحزمة الذهبية واحصل على وصول غير محدود شمرا أكاديميا
تسجيل مستخدم جديدMeasurement of $Upsilon$(1S+2S+3S) production in $p$$+$$p$ and Au$+$Au collisions at $sqrt{s_{_{NN}}}=200$ GeV
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Measurements of bottomonium production in heavy ion and $p$$+$$p$ collisions at the Relativistic Heavy Ion Collider (RHIC) are presented. The inclusive yield of the three $Upsilon$ states, $Upsilon(1S+2S+3S)$, was measured in the PHENIX experiment via electron-positron decay pairs at midrapidity for Au$+$Au and $p$$+$$p$ collisions at $sqrt{s_{_{NN}}}=200$ GeV. The $Upsilon(1S+2S+3S)rightarrow e^+e^-$ differential cross section at midrapidity was found to be $B_{rm ee} dsigma/dy =$ 108 $pm$ 38 (stat) $pm$ 15(syst) $pm$ 11 (luminosity) pb in $p$$+$$p$ collisions. The nuclear modification factor in the 30% most central Au$+$Au collisions indicates a suppression of the total $Upsilon$ state yield relative to the extrapolation from $p$$+$$p$ collision data. The suppression is consistent with measurements made by STAR at RHIC and at higher energies by the CMS experiment at the Large Hadron Collider.
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The three Upsilon states, Upsilon(1S+2S+3S), are measured in d+Au and p+p collisions at sqrt(s_NN)=200 GeV and rapidities 1.2<|y|<2.2 by the PHENIX experiment at the Relativistic Heavy-Ion Collider. Cross sections for the inclusive Upsilon(1S+2S+3S)
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