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arXiv · 1203.4071

Examination of scaling of Hanbury-Brown--Twiss radii with charged particle multiplicity

Gunnar Graef·Qingfeng Li·Marcus Bleicher
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Abstract

In the light of the recent LHC data on proton-proton and lead-lead collisions we examine the question of the multiplicity scaling of HBT radii in relativistic nuclei and particle interactions. Within the UrQMD transport approach we study a large variety of system sizes at different beam energies and extract the HBT radii. In the calculation, we find a good scaling of the radii as a function of charged particle multiplicity, if the change in the multiplicity is caused by a change of centrality at the same energy. However, the scaling is only approximate when the energy, $\sqrt{s}$, is changed and breaks down when comparing pp to AA reactions.

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Gunnar Graef, Qingfeng Li, Marcus Bleicher. 2012-03-19. Examination of scaling of Hanbury-Brown--Twiss radii with charged particle multiplicity. https://doi.org/10.1103/physrevc.85.044901

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