2009/08/26 by A. Kisiel, Adam Kisiel, Kisiel, Adam +3
Mathematics · Physics and Astronomy · #FOS: Physical sciences #High-Energy Particle Collisions Research #Nuclear Theory (nucl-th) #Stochastic processes and statistical mechanics #Theoretical and Computational Physics #nucl-th
paper · pdf · doi:10.48550/arxiv.0908.3830
9 pages, 11 figures ver2: added CERN report no., added references to relevant previous works on transport models
openalex publication_date 2009/08/26 · arxiv created 2009/09/09 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
Femtoscopy measures space-time characteristics of the particle emitting source created in relativistic heavy-ion collisions. It is argued that collective behavior of matter (radial flow) produces specific femtoscopic signatures. The one that is best known, the mT dependence of the pion ``HBT radii'', can be explained by the alternative scenario of temperature gradients in an initial state thermal model. We identify others that can invalidate such alternatives, such as non-identical particle correlations and mT scaling for particles of higher mass. Studies with a simple rescattering code show that as the interaction cross-section is increased the system develops collective behavior and becomes more thermalized at the same time, the two effects being the natural consequence of increased number of particle rescatterings. Repeating calculations with a more realistic rescattering model confirmed all of these conclusions and provided deeper insight into the mechanisms of collectivity buildup, showing a preference for a thermal model with uniform temperature.