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arXiv · 1407.0629

System-size and energy dependence of particle momentum spectra: The UrQMD analysis of p+p and Pb+Pb collisions

V. Yu. Vovchenko·D. V. Anchishkin·M. I. Gorenstein
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Abstract

The UrQMD transport model is used to study a system-size and energy dependence of the pion production in high energy collisions. New data of the NA61/SHINE Collaboration on spectra of negatively charged pions in proton-proton interactions at SPS energies are considered. These results are compared with the corresponding data of the NA49 Collaboration in central Pb+Pb collisions at the same collision energies per nucleon. Mean pion multiplicity per participant nucleon, inverse slope parameter of the transverse momentum spectra, and width of rapidity distribution are investigated. A role of isospin effects is discussed. We find that the UrQMD model predicts a non-monotonous behavior of mean transverse mass with collision energy for positively charged pions at the mid-rapidity in inelastic proton-proton interactions. This will be checked soon experimentally by NA61/SHINE Collaboration.

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V. Yu. Vovchenko, D. V. Anchishkin, M. I. Gorenstein. 2014-08-14. System-size and energy dependence of particle momentum spectra: The UrQMD analysis of p+p and Pb+Pb collisions. https://doi.org/10.1103/physrevc.90.024916

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