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Dissipation and fragmentation of low-Q^2 scattered partons in Au-Au collisions at RHIC

STAR Collaboration·R. L. Ray·M. Daugherity
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Abstract

Two-particle correlations and event-wise fluctuations in transverse momentum p_t are reported for Au-Au collisions at sqrt{s_{NN}} = 62 and 200 GeV on pseudorapidity (eta) and azimuth (phi). Distributions of all pairs of particles (no leading trigger particle) reveal jet-like correlations, or peaks at pair-wise opening angles of order 1 radian or less. The width of this same-side correlation peak increases dramatically on pseudorapidity and decreases on azimuth for increasing collision centrality. Evolution of the same-side peak with centrality suggests dissipation of low-Q^2 partons via strong coupling to an expanding bulk medium. p_t correlations, which provide access to temperature and/or velocity distributions in the colliding system, are also presented.

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STAR Collaboration, R. L. Ray, M. Daugherity. 2006-01-20. Dissipation and fragmentation of low-Q^2 scattered partons in Au-Au collisions at RHIC. https://doi.org/10.1556/aph.27.2006.2-3.18

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