Meson and baryon elliptic flow at high pT from parton coalescence
نویسنده
چکیده
The large and saturating differential elliptic flow v2(p⊥) observed in Au + Au reactions at RHIC so far could only be explained assuming an order of magnitude denser initial parton system than estimated from perturbative QCD. Hadronization via parton coalescence can resolve this “opacity puzzle” because it enhances hadron elliptic flow at large p⊥ relative to that of partons at the same transverse momentum. An experimentally testable consequence of the coalescence scenario is that v2(p⊥) saturates at about 50% higher values for baryons than for mesons. In addition, if strange quarks have weaker flow than light quarks, hadron v2 at high p⊥ decreases with relative strangeness content. PACS numbers: 12.38.Mh; 24.85.+p; 25.75.Gz; 25.75.-q
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