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

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 نشر من قبل Kai O. Schweda
 تاريخ النشر 2009
  مجال البحث
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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 possible participation in the collective flow of the QCD-medium constitute a powerful probe for thermalization. We present studies with PYTHIA for p+p collisions at the top LHC energy of $sqrt{s}$ = 14 TeV applying the two-particle transverse momentum correlator $<Delta p_{t,1}, Delta p_{t,2}>$ to pairs of heavy-quark hadrons and their semi-leptonic decay products as a function of their relative azimuth. Modifications or even the complete absence of initially existing correlations in Pb+Pb collisions might indicate thermalization at the partonic level.

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