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تسجيل مستخدم جديدCoherent and incoherent Upsilon production in ultraperipheral collisions at the Large Hadron Collider
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The exclusive photoproduction of $Upsilon (nS)$ states were calculated in ultra-peripheral collisions for coherent and incoherent process in PbPb at $sqrt{s_{NN}}$= 5.5 TeV. Different dipole models were compared in the theoretical framework of light-cone color dipole formalism. Moreover, it was calculated the differential cross section for the Upsilon states and their total cross section for two intervals of rapidity: $|y|leq 4$ 4 and $ 2 le$ y $le 4.5$. A systematic study is done on the theoretical uncertainties associated to the production and predictions are presented for the first time for the incoherent cross section of the radially excited states.
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