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arXiv · 1011.5649

Universal properties of particle production in the soft limit p_T -> 0

Wolfgang Ochs·Valery A. Khoze·M. G. Ryskin
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Abstract

The momentum spectra of particles in different high energy processes, such as e^+e^- annihilation, pp and nuclear collisions in the limit p,p_T -> 0 exhibit similar properties because of the dominant role of coherent soft gluon bremsstrahlung. We observe the following general features: the inclusive particle density approaches a limiting behaviour and becomes independent of primary collision energy; furthermore, it becomes proportional to the QCD colour factors C_A,C_F which appear in the Born term for the respective minimal partonic processes. In this limit, nuclear collisions reach with good accuracy participant (``wounded nucleon'') scaling. Particle ratios in the low momentum region display a universal behaviour. Future measurements at the LHC will provide crucial tests for the contributions from additional incoherent multi-component processes.

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Wolfgang Ochs, Valery A. Khoze, M. G. Ryskin. 2010-11-25. Universal properties of particle production in the soft limit p_T -> 0. https://arxiv.org/abs/1011.5649

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