Multi-Energy Analysis of Baryon Stopping: Extracting Non-Equilibrium Dynamics via Stochastic Rapidity Diffusion
Abstract
We present a comprehensive extraction of baryon stopping transport properties derived from net-proton transverse momentum (pT) spectra across a broad energy range, from Elab = 2.0 A GeV (√(sNN) = 2.70 GeV) to √(sNN) = 62.4 GeV in central heavy-ion collisions (≤ 10% centrality). By performing a systematic, multi-rapidity blast-wave analysis of experimental invariant yields, we extract the continuous rapidity density profile ρnet(y) and the transverse momentum broadening profile ⟨ pT2 ⟩net(y). Utilizing a stochastic diffusion framework governed by relativistic Fokker-Planck dynamics, we analytically derive the longitudinal friction coefficient αbw, the rapidity diffusion coefficient Dy, the longitudinal relaxation time τrelax, and the associated longitudinal Reynolds number ReL. Our extracted central stopping fractions demonstrate qualitative consistency with the previous published two source thermal calculations. Crucially, the excitation function of ReL reveals a drop by a factor of ∼ 163, from ReL ≈ 4.88 at √(sNN) = 2.70 GeV to ReL ≈ 0.03 at 62.4 GeV. This provides a clear macroscopic baseline for the crossover from inertial, advection-dominated baryon stopping to thermal, diffusion-dominated nuclear transparency, establishing a solid data-driven baseline for the topological baryon junction dynamics and high-μB matter anticipated at upcoming facilities, including FAIR, NICA, and the CEE.
Related
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- Slow-fast dynamics of the McKean model with stochastic resetting and diffusion
- Extracting Chern numbers from the equilibrium transport noise of multiband bosons
- Diffusion under competing bulk and surface stopping mechanisms
- Identifying Non-Ideal Reaction-Diffusion Systems Unable to Maintain Diffusion Out-of-Equilibrium
BibTeX
@misc{thakur2026multienergy,
title = {{Multi-Energy Analysis of Baryon Stopping: Extracting Non-Equilibrium Dynamics via Stochastic Rapidity Diffusion}},
author = {Dhananjaya Thakur},
howpublished = {arXiv},
year = {2026},
month = oct,
doi = {10.48550/arxiv.2610.29499},
eprint = {2610.29499},
archivePrefix = {arXiv},
url = {https://arxiv.org/abs/2610.29499},
note = {CC BY 4.0},
}
RIS
TY - UNPB
TI - Multi-Energy Analysis of Baryon Stopping: Extracting Non-Equilibrium Dynamics via Stochastic Rapidity Diffusion
AU - Dhananjaya Thakur
PY - 2026
DA - 2026/10/21
PB - arXiv
DO - 10.48550/arxiv.2610.29499
UR - https://arxiv.org/abs/2610.29499
AB - We present a comprehensive extraction of baryon stopping transport properties derived from net-proton transverse momentum (p_T) spectra across a broad energy range, from E_lab = 2.0 A GeV (√(s_NN) = 2.70 GeV) to √(s_NN) = 62.4 GeV in central heavy-ion collisions (≤ 10% centrality). By performing a systematic, multi-rapidity blast-wave analysis of experimental invariant yields, we extract the continuous rapidity density profile ρ_net(y) and the transverse momentum broadening profile ⟨ p_T^2 ⟩_net(y). Utilizing a stochastic diffusion framework governed by relativistic Fokker-Planck dynamics, we analytically derive the longitudinal friction coefficient α_bw, the rapidity diffusion coefficient D_y, the longitudinal relaxation time τ_relax, and the associated longitudinal Reynolds number Re_L. Our extracted central stopping fractions demonstrate qualitative consistency with the previous published two source thermal calculations. Crucially, the excitation function of Re_L reveals a drop by a factor of ∼ 163, from Re_L ≈ 4.88 at √(s_NN) = 2.70 GeV to Re_L ≈ 0.03 at 62.4 GeV. This provides a clear macroscopic baseline for the crossover from inertial, advection-dominated baryon stopping to thermal, diffusion-dominated nuclear transparency, establishing a solid data-driven baseline for the topological baryon junction dynamics and high-μ_B matter anticipated at upcoming facilities, including FAIR, NICA, and the CEE.
ER -