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The energy dependence of $p_t$ angular correlations inferred from mean-$p_{t}$ fluctuation scale dependence in heavy ion collisions at the SPS and RHIC

J. Adams
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Abstract

We present the first study of the energy dependence of $p_t$ angular correlations inferred from event-wise mean transverse momentum $ $ fluctuations in heavy ion collisions. We compare our large-acceptance measurements at CM energies $\sqrt{s_{NN}} =$ 19.6, 62.4, 130 and 200 GeV to SPS measurements at 12.3 and 17.3 GeV. $p_t$ angular correlation structure suggests that the principal source of $p_t$ correlations and fluctuations is minijets (minimum-bias parton fragments). We observe a dramatic increase in correlations and fluctuations from SPS to RHIC energies, increasing linearly with $\ln \sqrt{s_{NN}}$ from the onset of observable jet-related $ $ fluctuations near 10 GeV.

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J. Adams. 2006-12-07. The energy dependence of $p_t$ angular correlations inferred from mean-$p_{t}$ fluctuation scale dependence in heavy ion collisions at the SPS and RHIC. https://doi.org/10.1088/0954-3899%2F34%2F3%2F004

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