Simultaneous Determination of Fragmentation Functions and Test on Momentum Sum Rule

We perform a simultaneous global analysis of hadron fragmentation functions (FFs) to various charged hadrons (<a:math xmlns:a="http://www.w3.org/1998/Math/MathML" display="inline"><a:msup><a:mi>π</a:mi><a:mo>±</a:mo></a:msup></a:math>, <c:math xmlns:c="http://www.w3.org/1998/Math/MathML" display="inline"><c:msup><c:mi>K</c:mi><c:mo>±</c:mo></c:msup></c:math>, and <e:math xmlns:e="http://www.w3.org/1998/Math/MathML" display="inline"><e:mi>p</e:mi><e:mo>/</e:mo><e:mover accent="true"><e:mi>p</e:mi><e:mo stretchy="false">¯</e:mo></e:mover></e:math>) at next-to-leading order in QCD. The world data include results from electron-positron single-inclusive annihilation, semi-inclusive deep inelastic scattering, as well as proton-proton collisions including jet fragmentation measurements for the first time, which lead to strong constraints on the gluon fragmentations. By carefully selecting hadron kinematics to ensure the validity of QCD factorization and the convergence of perturbative calculations, we achieve a satisfying best fit with <i:math xmlns:i="http://www.w3.org/1998/Math/MathML" display="inline"><i:msup><i:mi>χ</i:mi><i:mn>2</i:mn></i:msup><i:mo>/</i:mo><i:mrow><i:mi mathvariant="normal">d</i:mi><i:mo>.</i:mo><i:mi mathvariant="normal">o</i:mi><i:mo>.</i:mo><i:mi mathvariant="normal">f</i:mi><i:mo>.</i:mo></i:mrow><i:mo>=</i:mo><i:mn>0.90</i:mn></i:math>. The total momentum of <n:math xmlns:n="http://www.w3.org/1998/Math/MathML" display="inline"><n:mi>u</n:mi></n:math>, <p:math xmlns:p="http://www.w3.org/1998/Math/MathML" display="inline"><p:mi>d</p:mi></p:math> quarks and gluon carried by light charged hadrons have been determined precisely, urging precision determinations of FFs to neutral hadrons for a test of fundamental sum rules in QCD fragmentation. Published by the American Physical Society 2024