Characterizing pT-differential Radial-Flow Fluctuations in Au+Au Collisions at FAIR with a Multi-Phase Transport Model
Abstract
We report the first predictions of the transverse-momentum (pT)-differential radial-flow fluctuation observable, vzpT, in Au+Au collisions at the top SIS100 energy, snn=4.9~GeV, which will be available at the FAIR accelerator complex. Radial flow and its fluctuations are studied for different centrality intervals and reference-pT selections to investigate the properties and robustness of the calculated long-range correlation. vzpT displays a characteristic evolution from negative values at low pT to positive values at higher pT. The integrated v0, obtained with different reference-pT intervals, follows a common trend, with an approximately inverse-square-root dependence on the inclusive charged-particle multiplicity (nch). The vzpT signal changes little when the pseudorapidity gap is varied between 0.2 and 0.8, or when the edges of the reference-pT interval are varied, in the bulk region. For identified particles, the pion and proton vzpT are ordered at low pT, qualitatively similar to the mass ordering seen at higher energies. However, unlike at higher collision energies, vzpT does not exhibit constituent-quark scaling, so the results do not support an interpretation in terms of partonic collectivity. These results provide constraints on the evolution of radial correlations toward lower collision energies and motivate comparisons with complementary observables to clarify their connection to collective dynamics.
Related
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BibTeX
@misc{thakur2026characterizing,
title = {{Characterizing $\pT$-differential Radial-Flow Fluctuations in Au+Au Collisions at FAIR with a Multi-Phase Transport Model}},
author = {Sanchari Thakur and Partha Pratim Bhaduri},
howpublished = {arXiv},
year = {2026},
month = oct,
doi = {10.48550/arxiv.2610.41607},
eprint = {2610.41607},
archivePrefix = {arXiv},
url = {https://arxiv.org/abs/2610.41607},
}
RIS
TY - UNPB
TI - Characterizing pT-differential Radial-Flow Fluctuations in Au+Au Collisions at FAIR with a Multi-Phase Transport Model
AU - Sanchari Thakur
AU - Partha Pratim Bhaduri
PY - 2026
DA - 2026/10/30
PB - arXiv
DO - 10.48550/arxiv.2610.41607
UR - https://arxiv.org/abs/2610.41607
AB - We report the first predictions of the transverse-momentum (pT)-differential radial-flow fluctuation observable, vzpT, in Au+Au collisions at the top SIS100 energy, snn=4.9~GeV, which will be available at the FAIR accelerator complex. Radial flow and its fluctuations are studied for different centrality intervals and reference-pT selections to investigate the properties and robustness of the calculated long-range correlation. vzpT displays a characteristic evolution from negative values at low pT to positive values at higher pT. The integrated v_0, obtained with different reference-pT intervals, follows a common trend, with an approximately inverse-square-root dependence on the inclusive charged-particle multiplicity (nch). The vzpT signal changes little when the pseudorapidity gap is varied between 0.2 and 0.8, or when the edges of the reference-pT interval are varied, in the bulk region. For identified particles, the pion and proton vzpT are ordered at low pT, qualitatively similar to the mass ordering seen at higher energies. However, unlike at higher collision energies, vzpT does not exhibit constituent-quark scaling, so the results do not support an interpretation in terms of partonic collectivity. These results provide constraints on the evolution of radial correlations toward lower collision energies and motivate comparisons with complementary observables to clarify their connection to collective dynamics.
ER -