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arXiv · 2609.15168

Determination of charged pion unpolarised TMDPDFs from Drell-Yan measurements

Wen-Chen Chang·Chia-Yu Hsieh·Chung-Wen Kao·C. -J. David Lin·Valentin Moos·Wayne Morris
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Abstract

We present an extraction of the unpolarised transverse momentum dependent (TMD) parton distribution functions (PDFs) for the valence quarks in the pion from experimental mea- surements of the Drell-Yan process. The procedure adopted in this project relies on the framework of TMD factorisation, and the inputs of nucleon TMDPDF, pion collinear PDF, as well as the Collins-Soper kernel. The non-perturbative behaviour of the TMDPDFs is parameterised using an ansatz function that contains three unknown parameters and implements an exponential decay at large transverse distances. This work employs the most recent results in perturbation theory, and utilises a precise estimation of the nucleon TMDPDF. We perform an investigation of data used in the fit. This investigation leads to important observations regarding the effects of the kinematics and binning methods in the experimental data. Our results agree qualitatively with the previous determinations from phenomenology and a lattice computation

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Wen-Chen Chang, Chia-Yu Hsieh, Chung-Wen Kao, C. -J. David Lin, Valentin Moos, Wayne Morris. 2026-09-14. Determination of charged pion unpolarised TMDPDFs from Drell-Yan measurements. https://arxiv.org/abs/2609.15168

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