Confronting Color Glass Condensate at next-to-leading order with HERA data

TL;DR

This paper performs a comprehensive NLO analysis of HERA data to extract initial conditions for the BK equation, improving theoretical precision and uncertainty estimation in the Color Glass Condensate framework.

Contribution

It extends previous analyses to full NLO+NLL accuracy, combining impact factors with the NLO BK equation and employing Bayesian methods for uncertainty quantification.

Findings

Extracted posterior distributions for BK initial conditions.

Quantified theoretical uncertainties in dipole amplitude.

Enhanced the precision of CGC calculations at NLO.

Abstract

We perform a global analysis of HERA total inclusive cross section and charm quark production data to extract the non-perturbative initial condition for the next-to-leading order Balitsky-Kovchegov (BK) equation. We extend our previous analyses to full next-to-leading order + next-to-leading logarithm (NLO+NLL) accuracy by combining the NLO DIS impact factors with the NLO BK equation that includes the resummation of large double and single logarithms. The developed Bayesian setup extracts the posterior that describes the distribution of the parameters that best fit the data. The posterior distribution allows for estimates of the theoretical uncertainty of the dipole amplitude and, hence, offers a streamlined method for propagating uncertainties in the BK initial condition in NLO CGC calculations.