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arXiv · hep-ph/9404237

Multiplicities for LHC Nuclear Collisions Using HERA Structure Functions

K. J. Eskola·K. Kajantie·P. V. Ruuskanen
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Abstract

We compute in QCD perturbation theory the transverse energy carried by gluons, quarks and antiquarks with $p_T\ge p_0\approx 2$ GeV in Pb+Pb collisions at $\sqrt{s}=5500$ $A$GeV by using structure functions compatible with the small-$x$ increase observed at HERA. This gives a perturbative estimate for the energy and entropy density of the bulk system at times $τ\sim 0.1$ fm. The predicted initial gluon entropy density gives a lower limit of about 2200...3400 for the final charged multiplicity. Sources of further entropy increase are discussed.

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K. J. Eskola, K. Kajantie, P. V. Ruuskanen. 1994-04-08. Multiplicities for LHC Nuclear Collisions Using HERA Structure Functions. https://doi.org/10.1016/0370-2693(94)90878-8

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