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تسجيل مستخدم جديد$rm{J}/psi$ production at low transverse momentum in p+p and d+Au collisions at $sqrt{s_{NN}}$ = 200 GeV
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We report on the measurement of $rm{J}/psi$ production in the dielectron channel at mid-rapidity (|y|<1) in p+p and d+Au collisions at $sqrt{s_{NN}}$ = 200 GeV from the STAR experiment at the Relativistic Heavy Ion Collider. The transverse momentum $p_{T}$ spectra in p+p for $p_{T}$ < 4 GeV/c and d+Au collisions for $p_{T}$ < 3 GeV/c are presented. These measurements extend the STAR coverage for $rm{J}/psi$ production in p+p collisions to low $p_{T}$. The $<p_{T}^{2}>$ from the measured $rm{J}/psi$ invariant cross section in p+p and d+Au collisions are evaluated and compared to similar measurements at other collision energies. The nuclear modification factor for $rm{J}/psi$ is extracted as a function of $p_{T}$ and collision centrality in d+Au and compared to model calculations using the modified nuclear Parton Distribution Function and a final-state $rm{J}/psi$ nuclear absorption cross section.
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