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Heavy--quark momentum correlations as a sensitive probe of thermalization

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 نشر من قبل Kai O. Schweda
 تاريخ النشر 2009
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In high-energy nuclear collisions the degree of thermalization at the partonic level is a key issue. Due to their large mass, heavy-quarks and their participation in the collective flow of the QCD medium constitute a powerful tool to probe thermalization. We propose measuring azimuthal correlations of heavy-quark hadrons and products from their semi-leptonic decay. Modifications or even the complete absence of initially, e.g. in p-p collisions, existing azimuthal correlations in Pb-Pb collisions might indicate thermalization at the partonic level. We present studies with PYTHIA for p-p collisions at the top LHC energy using the two-particle transverse momentum correlator ${<overline{Delta}p_{t,1}overline{Delta}p_{t,2}>}$ as a sensitive measure of azimuthal correlations.



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