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Transverse-momentum $p_t$ correlations on $(η,ϕ)$ from mean-$p_{t}$ fluctuations in Au-Au collisions at $\sqrt{s_{NN}} = $ 200 GeV

STAR Collaboration·J. Adams
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Abstract

We present first measurements of the pseudorapidity and azimuth $(η,ϕ)$ bin-size dependence of event-wise mean transverse momentum $ $ fluctuations for Au-Au collisions at $\sqrt{s_{NN}} = 200$ GeV. We invert that dependence to obtain $p_t$ autocorrelations on differences $(η_Δ,ϕ_Δ)$ interpreted to represent velocity/temperature distributions on ($η,ϕ$). The general form of the autocorrelations suggests that the basic correlation mechanism is parton fragmentation. The autocorrelations vary strongly with collision centrality, which suggests that fragmentation is strongly modified by a dissipative medium in the more central Au-Au collisions relative to peripheral or p-p collisions. \\

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STAR Collaboration, J. Adams. 2006-04-11. Transverse-momentum $p_t$ correlations on $(η,ϕ)$ from mean-$p_{t}$ fluctuations in Au-Au collisions at $\sqrt{s_{NN}} = $ 200 GeV. https://doi.org/10.1088/0954-3899%2F32%2F6%2Fl02

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