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arXiv · 1907.02573

Global characteristics of the medium produced in ultra-high energy cosmic ray collisions

Abstract

Estimations of some geometrical and bulk parameters are presented for the matter produced in various type collisions with ultra-high energy cosmic ray (UHECR) particles. Results for multiplicity density at midrapidity, decoupling time, and energy density are discussed for small and larger collision systems. Based on the analytic functions suggested previously elsewhere, estimations for a wide set of space-time quantities are obtained for emission region created in various particle collisions at energies of UHECR. The space particle densities at freeze-out are derived also and allow the possibility of novel features for secondary particle production like Bose-Einstein condensation at least for nuclear interactions with UHECR particles. The estimations obtained for global and geometrical parameters indicate the creation of deconfined quark-gluon matter with large enough volume and lifetime even in light nuclear collisions at UHECR energies. These quantitative results can be important for both the future collider experiments at center-of-mass energy frontier and the improvement of the phenomenological models for development of the cosmic ray cascades in ultra-high energy domain.

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V. A. Okorokov. 2020-02-22. Global characteristics of the medium produced in ultra-high energy cosmic ray collisions. https://doi.org/10.1134/s1063778819660426

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