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Long-Range Multiplicity Correlations in Relativistic Heavy Ion Collisions as a Signal for Dense Partonic Matter

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 نشر من قبل Terence Tarnowsky
 تاريخ النشر 2012
  مجال البحث
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A dense form of matter is formed in relativistic heavy ion collisions. The constituent degrees of freedom in this dense matter are currently unknown. Long-range, forward-backward multiplicity correlations (LRC) are expected to arise due to multiple partonic interactions. Model independent and dependent arguments suggest that such correlations are due to multiple partonic interactions. These correlations are predicted in the context of the Dual Parton Model (DPM). The DPM describes soft partonic processes and hadronization. This model indicates that the underlying mechanism creating these long-range multiplicity correlations in the bulk matter is due to multiple partonic interactions. In this thesis, long-range multiplicity correlations have been studied in heavy ion (Au+Au and Cu+Cu) and hadron-hadron ({it pp}) collisions. The behavior has been studied as a function of pseudorapidity gap ($Deltaeta$) about $eta$ = 0, the centrality, atomic number, and incident energy dependence of the colliding particles. Strong, long-range correlations ($Deltaeta >$ 1.0) as a function of $Deltaeta$ are found for central collisions of %(full overlap) heavy ions at an energy of $sqrt{s_{NN}}$ = 200 GeV. This indicates substantial amounts of dense partonic matter are formed in central heavy ion collisions at an energy of $sqrt{s_{NN}}$ = 200 GeV.



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