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arXiv · 1710.09725

Collectivity without plasma in hadronic collisions

Christian Bierlich·Gösta Gustafson·Leif Lönnblad
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Abstract

We present a microscopic model for collective effects in high multiplicity proton--proton collisions, where multiple partonic subcollisions give rise to a dense system of strings. From lattice calculations we know that QCD strings are transversely extended, and we argue that this should result in a transverse pressure and expansion, similar to the flow in a deconfined plasma. The model is implemented in the PYTHIA8 Monte Carlo event generator, and we find that it can qualitatively reproduce the long range azimuthal correlations forming a near-side ridge in high multiplicity proton--proton events at LHC energies.

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Christian Bierlich, Gösta Gustafson, Leif Lönnblad. 2017-10-26. Collectivity without plasma in hadronic collisions. https://doi.org/10.1016/j.physletb.2018.01.069

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