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Instanton-induced Semi-hard Parton Interactions and Phenomenology of High Energy Hadron Collisions

G. W. Carter·D. M. Ostrovsky·E. V. Shuryak
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Abstract

We phenomenologically study whether partonic collisions responsible for the growth of hadron-hadron cross sections at high energy can be ascribed to instanton-induced processes. Although non-perturbative in nature, these interactions occur at the semi-hard scale $Q\sim 1-2$ GeV, and should therefore be described using information from deep inelastic leptonic scattering on the partonic constituents in nucleons, pions, and photons. After considering shadowing corrections in nucleon-nucleon scattering, we fix a free instanton tail suppression parameter and determine the effective quark-quark cross section. The resulting contributions to $NN$, $πN$, $γN$, and $γγ$ cross sections all $increase$ with energy differently, but in reasonable agreement with experimental data. We then proceed to an estimate of the number of such processes present in high energy Au-Au collisions at RHIC, finding that the amount of entropy produced by instanton/sphaleron events matches the observed amount.

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G. W. Carter, D. M. Ostrovsky, E. V. Shuryak. 2001-12-03. Instanton-induced Semi-hard Parton Interactions and Phenomenology of High Energy Hadron Collisions. https://doi.org/10.1103/physrevd.65.074034

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