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High-multiplicity pA collisions and the small-x effective action

A. Dumitru
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Abstract

I discuss the p_t distributions for high-multiplicity events originating from semi-classical variation of the gluon density of the proton.The multiplicity distribution measures the curvature of the effective action for the small-x gluon fields. For pA collisions at the RHIC and LHC colliders, semi-classically the multiplicity distribution reflects the distribution of saturation momenta of the proton but not that of the nucleus. The average transverse momentum in the central region grows with dN/dy, while the p_t distribution of leading hadrons in the proton fragmentation region should depend less on the multiplicity in the central region.

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A. Dumitru. 2002-10-29. High-multiplicity pA collisions and the small-x effective action. https://arxiv.org/abs/hep-ph/0210412

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