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$Doverline{D}$ momentum correlations versus relative azimuth as a sensitive probe for thermalization

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 نشر من قبل Kai O. Schweda
 تاريخ النشر 2009
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In high-energy nuclear collisions at LHC, where a QGP might be created, the degree of thermalization at the partonic level is a key issue. Due to their large mass, heavy quarks are a powerful tool to probe thermalization. We propose to measure azimuthal correlations of heavy-quark hadrons and their decay products. Changes or even the complete absence of these initially existing azimuthal correlations in $Pb-Pb$ collisions might indicate thermalization at the partonic level. We present studies with PYTHIA for $p-p$ collisions at 14 TeV using the two-particle transverse momentum correlator ${<overline{Delta}p_{t,1}overline{Delta}p_{t,2}>}$ as a sensitive measure of potential changes in these azimuthal correlations. Contributions from transverse radial flow are estimated.

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