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arXiv · 0911.3130

Identified high-$p_{T}$ spectra in Cu+Cu collisions at $\sqrt{s_{NN}}$=200 GeV

STAR Collaboration·B. I. Abelev
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Abstract

We report new results on identified (anti)proton and charged pion spectra at large transverse momenta (3<$p_{T}$<10 GeV/c) from Cu+Cu collisions at $\sqrt{s_{NN}}$=200 GeV using the STAR detector at the Relativistic Heavy Ion Collider (RHIC). This study explores the system size dependence of two novel features observed at RHIC with heavy ions: the hadron suppression at high-$p_{T}$ and the anomalous baryon to meson enhancement at intermediate transverse momenta. Both phenomena could be attributed to the creation of a new form of QCD matter. The results presented here bridge the system size gap between the available pp and Au+Au data, and allow the detailed exploration for the on-set of the novel features. Comparative analysis of all available 200 GeV data indicates that the system size is a major factor determining both the magnitude of the hadron spectra suppression at large transverse momenta and the relative baryon to meson enhancement.

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STAR Collaboration, B. I. Abelev. 2009-11-16. Identified high-$p_{T}$ spectra in Cu+Cu collisions at $\sqrt{s_{NN}}$=200 GeV. https://doi.org/10.1103/physrevc.81.054907

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