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arXiv · 1902.06048

Event-plane dependent away-side jet-like correlation shape in Au+Au collisions at $\sqrt{s_{NN}}=200$ GeV from STAR

Abstract

We employ a data-driven method to subtract the flow background of all harmonics by calculating the difference of the two-particle correlations between the close-region and far-region, determined depending on the pseudo-rapidity ($η$) distance from the region where an enhanced recoil transverse momentum ($P_x$) from a high-$p_T$ trigger particle is selected. We analyze the correlation shape as a function of the trigger particle azimuthal angle relative to the event-plane (EP) reconstructed from the beam-beam counters (BBCs) which are displaced by several units in $η$ from the mid-rapidity region. The large $η$ gap can effectively eliminate the auto-correlation between trigger particles and EP. We correct for the relatively large resolution effect from the BBC EP determination via an unfolding procedure. The width of unfolded away-side jet-like correlation increases with longer path-length, which is an indication of jet-medium interactions.

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Liang Zhang. 2019-02-16. Event-plane dependent away-side jet-like correlation shape in Au+Au collisions at $\sqrt{s_{NN}}=200$ GeV from STAR. https://doi.org/10.22323/1.345.0083

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