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

The available world deep-inelastic scattering (DIS) data on proton and deuteron structure functions <a:math xmlns:a="http://www.w3.org/1998/Math/MathML" display="inline"><a:msubsup><a:mi>F</a:mi><a:mn>2</a:mn><a:mi>p</a:mi></a:msubsup></a:math>, <c:math xmlns:c="http://www.w3.org/1998/Math/MathML" display="inline"><c:msubsup><c:mi>F</c:mi><c:mn>2</c:mn><c:mi>d</c:mi></c:msubsup></c:math>, and their ratios are leveraged to extract the free neutron <e:math xmlns:e="http://www.w3.org/1998/Math/MathML" display="inline"><e:msubsup><e:mi>F</e:mi><e:mn>2</e:mn><e:mi>n</e:mi></e:msubsup></e:math> structure function, the <g:math xmlns:g="http://www.w3.org/1998/Math/MathML" display="inline"><g:msubsup><g:mi>F</g:mi><g:mn>2</g:mn><g:mi>n</g:mi></g:msubsup><g:mo>/</g:mo><g:msubsup><g:mi>F</g:mi><g:mn>2</g:mn><g:mi>p</g:mi></g:msubsup></g:math> 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 <i:math xmlns:i="http://www.w3.org/1998/Math/MathML" display="inline"><i:msubsup><i:mi>F</i:mi><i:mn>2</i:mn><i:mi>n</i:mi></i:msubsup></i:math> dataset is utilized to evaluate the <k:math xmlns:k="http://www.w3.org/1998/Math/MathML" display="inline"><k:msup><k:mi>Q</k:mi><k:mn>2</k:mn></k:msup></k:math> dependence of the Gottfried sum rule and the nonsinglet <m:math xmlns:m="http://www.w3.org/1998/Math/MathML" display="inline"><m:mrow><m:msubsup><m:mrow><m:mi>F</m:mi></m:mrow><m:mrow><m:mn>2</m:mn></m:mrow><m:mrow><m:mi>p</m:mi></m:mrow></m:msubsup><m:mo>−</m:mo><m:msubsup><m:mrow><m:mi>F</m:mi></m:mrow><m:mrow><m:mn>2</m:mn></m:mrow><m:mrow><m:mi>n</m:mi></m:mrow></m:msubsup></m:mrow></m:math> moments. To facilitate replication of our study, as well as for general applications, we provide a comprehensive DIS database including all recent Jefferson Lab 6 GeV measurements, the extracted <o:math xmlns:o="http://www.w3.org/1998/Math/MathML" display="inline"><o:msubsup><o:mi>F</o:mi><o:mi>n</o:mi><o:mn>2</o:mn></o:msubsup></o:math>, a modified CTEQ-JLab global parton distribution function fit named CJ15nlo_mod, and grids with calculated proton, neutron, and deuteron DIS structure functions.