Extraction of the neutron F2 structure function from inclusive proton and deuteron deep-inelastic scattering data

TL;DR

This paper extracts the neutron F2 structure function from proton and deuteron deep-inelastic scattering data, carefully accounting for nuclear effects and uncertainties, and provides a comprehensive dataset and tools for further research.

Contribution

It introduces a new method for extracting the neutron F2 structure function with improved uncertainty quantification and makes the data and tools publicly available.

Findings

Extracted neutron F2 structure function with quantified uncertainties

Evaluated Q2 dependence of the Gottfried sum rule

Provided a comprehensive DIS database and modified PDF fit

Abstract

The available world deep-inelastic scattering data on proton and deuteron structure functions F2p, F2d, and their ratios, are leveraged to extract the free neutron F2n structure function, the F2n/F2p ratio, and associated uncertainties using the latest nuclear effect calculations in the deuteron. Special attention is devoted to the normalization of the proton and deuteron experimental datasets and to the treatment of correlated systematic errors, as well as the quantification of procedural and theoretical uncertainties. The extracted F2n dataset is utilized to evaluate the Q2 dependence of the Gottfried sum rule and the nonsinglet F2p - F2n moments. To facilitate replication of our study, as well as for general applications, a comprehensive DIS database including all recent JLab 6 GeV measurements, the extracted F2n, a modified CTEQ-JLab global PDF fit named CJ15nlo_mod, and grids with calculated proton, neutron and deuteron DIS structure functions at next-to-leading order, are discussed and made publicly available.