Probing the Energy Evolution and Hadronic Cascade Time Dependence of Forward-Backward Multiplicity Correlations in pp Collisions at √s = 0.9--$13.6$~TeV with AMPT
Abstract
Forward-backward (FB) multiplicity correlations are studied in proton--proton collisions at centre-of-mass energies of √s = 0.9, $2.76$, $5.02$, $7$, $13$, and $13.6$~TeV using the AMPT model in its default (DF) and string melting (SM) configurations. The coefficient bcorr is obtained for windows separated in pseudorapidity and azimuth, and its variation with the pseudorapidity gap, window width, collision energy, transverse momentum interval, and hadronic cascade time τHC is investigated. The simulated results are compared with the available ALICE measurements, and the model is validated against experimental pseudorapidity densities and charged-pion transverse momentum spectra. The correlation strength is found to decrease gradually with increasing pseudorapidity gap while retaining a substantial pedestal, to rise non-linearly with the window width, and to increase substantially with collision energy. The DF configuration yields systematically larger values of bcorr than the SM configuration, while the SM configuration provides the better description of the ALICE data at $0.9$ and $2.76$~TeV and the DF configuration at $7$~TeV. In the lowest transverse momentum intervals the deviations from the data are largest for both configurations. The hadronic cascade time is varied within the SM configuration over τHC = 0.6, $5$, $15$, and $30fm/c$. A monotonic reduction of bcorr with increasing τHC is observed at all energies and for all window widths, with the ordering of the curves preserved throughout. The effect is modest but statistically significant. These results indicate that the FB correlation strength is primarily imprinted at the partonic stage and only mildly diluted by the subsequent hadronic evolution.
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BibTeX
@misc{dhar2026probing,
title = {{Probing the Energy Evolution and Hadronic Cascade Time Dependence of Forward-Backward Multiplicity Correlations in pp Collisions at $\sqrts = 0.9$--$13.6$~TeV with AMPT}},
author = {Dibakar Dhar and Tumpa Biswas and Prabir Kumar Haldar},
howpublished = {arXiv},
year = {2026},
month = oct,
doi = {10.48550/arxiv.2610.25154},
eprint = {2610.25154},
archivePrefix = {arXiv},
url = {https://arxiv.org/abs/2610.25154},
}
RIS
TY - UNPB
TI - Probing the Energy Evolution and Hadronic Cascade Time Dependence of Forward-Backward Multiplicity Correlations in pp Collisions at √s = 0.9--$13.6$~TeV with AMPT
AU - Dibakar Dhar
AU - Tumpa Biswas
AU - Prabir Kumar Haldar
PY - 2026
DA - 2026/10/18
PB - arXiv
DO - 10.48550/arxiv.2610.25154
UR - https://arxiv.org/abs/2610.25154
AB - Forward-backward (FB) multiplicity correlations are studied in proton--proton collisions at centre-of-mass energies of √s = 0.9, $2.76$, $5.02$, $7$, $13$, and $13.6$~TeV using the AMPT model in its default (DF) and string melting (SM) configurations. The coefficient b_corr is obtained for windows separated in pseudorapidity and azimuth, and its variation with the pseudorapidity gap, window width, collision energy, transverse momentum interval, and hadronic cascade time τ_HC is investigated. The simulated results are compared with the available ALICE measurements, and the model is validated against experimental pseudorapidity densities and charged-pion transverse momentum spectra. The correlation strength is found to decrease gradually with increasing pseudorapidity gap while retaining a substantial pedestal, to rise non-linearly with the window width, and to increase substantially with collision energy. The DF configuration yields systematically larger values of b_corr than the SM configuration, while the SM configuration provides the better description of the ALICE data at $0.9$ and $2.76$~TeV and the DF configuration at $7$~TeV. In the lowest transverse momentum intervals the deviations from the data are largest for both configurations. The hadronic cascade time is varied within the SM configuration over τ_HC = 0.6, $5$, $15$, and $30fm/c$. A monotonic reduction of b_corr with increasing τ_HC is observed at all energies and for all window widths, with the ordering of the curves preserved throughout. The effect is modest but statistically significant. These results indicate that the FB correlation strength is primarily imprinted at the partonic stage and only mildly diluted by the subsequent hadronic evolution.
ER -