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The Instanton/Sphaleron Mechanism of Prompt Gluon Production in High Energy Heavy Ion Collisions at RHIC

Edward V. Shuryak
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Abstract

We argue that if the growing part of hadron-hadron cross section (described phenomenologically by the supercritical soft Pomeron) is due to instanton/sphaleron mechanism, one should find certain qualitative features of the produced cluster which differ from the usual string fragmentation. Furthermore, we suggest that this mechanism should be even more important for heavy ion collisions in the RHIC energy domain. Large number of parton-parton collisions should result in hundreds of produced sphaleron-like gluomagnetic clusters per unit rapidity. Unlike perturbative gluons (or mini-jets), these {\em classically unstable} objects promptly decay into several gluons and quarks in mini-explosions, leading to very rapid entropy generation. This may help to explain why the QGP seem to be produced at RHIC so early. We further argue that this mechanism cannot be important at higher energies (LHC), where perturbative description should apply.

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Edward V. Shuryak. 2001-06-25. The Instanton/Sphaleron Mechanism of Prompt Gluon Production in High Energy Heavy Ion Collisions at RHIC. https://doi.org/10.1016/s0370-2693(01)00892-9

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