Determine whether the residual nuclear-modification enhancement is a lattice artifact

Determine whether the approximately ten-percent enhancement of the cross-section-normalized minimum-bias $R_{pA}^{\sigma}$ above unity is caused by finite-lattice-spacing artifacts or has a physical origin by repeating the analysis at finer lattice spacing across the Bayesian posterior.

Background

The cross-section-normalized nuclear modification factor RpAσR_{pA}^{\sigma} substantially reduces the uncertainty associated with the inelastic nucleon-nucleon cross section, but the calculation still shows an approximately ten-percent enhancement above unity. The authors note that this residual could arise from lattice discretization effects, although a physical explanation cannot be excluded.

Resolving the issue requires rerunning the full Bayesian posterior with a finer lattice spacing, which is computationally expensive because the computational cost scales inversely with the cube of the lattice spacing.

References

The 10\% enhancement in $R_{pA}{\sigma}$ observed in \cref{fig:RAA_pPb_MB_sigma} may arise from residual lattice effects, which we discuss in \cref{sec:dependence_of_results_on_lattice_spacing}, or may have a physical origin. Disentangling these possibilities would require running the entire Bayesian posterior at a finer lattice spacing, which is computationally expensive because the computation time scales as the inverse cube of the lattice spacing. We leave such an investigation for future work.

— Centrality-dependent nuclear modification from hard-soft correlations in the glasma  (2609.29886 - Faraday et al., 24 Sep 2026) in Section 4, Minimum-bias nuclear modification factor