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Transverse momentum and pseudorapidity dependences of $bm{Mach-like}$ correlations for central Au + Au collisions at $sqrt{s_{NN}}$ = 200 GeV

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 نشر من قبل Yu-Gang Ma
 تاريخ النشر 2007
  مجال البحث
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The transverse momentum and pseudorapidity dependences of partonic {`it{Mach-like}} shock wave have been studied by using a multi-phase transport model (AMPT) with both partonic and hadronic interactions. The splitting parameter $D$, i.e. half distance between two splitting peaks on away side in di-hadron azimuthal angular ($Deltaphi$) correlations, slightly increases with the transverse momentum of associated hadrons ($p^{assoc}_T$), which is consistent with preliminary experimental trend, owing to different interaction-lengths/numbers between wave partons and medium in strong parton cascade. On the other hand, the splitting parameter $D$ as a function of pseudorapidity of associated hadrons ($eta^{assoc}$), keeps flat in mid-pseudorapidity region and rapidly drops in high-pseudorapidity region, which is as a result of different violent degrees of jet-medium interactions in the medium that has different energy densities in the longitudinal direction. It is proposed that the research on the properties of {`it{Mach-like}} correlation can shed light on the knowledge of both partonic and hadronic interactions at RHIC.

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