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arXiv · 2502.11807

Quark Transverse Spin-Momentum Correlation of the Nucleon from Lattice QCD: The Boer-Mulders Function

Lingquan Ma·Jun Hua·Andreas Schäfer·Hai-Tao Shu·Yushan Su·Peng Sun·Lisa Walter·Wei Wang·Xiaonu Xiong·Yi-Bo Yang·Jian-Hui Zhang·Qi-An Zhang
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Abstract

We present the first lattice QCD calculation of the quark transverse spin-momentum correlation, i.e., the naive time-reversal-odd Boer-Mulders function, of the nucleon, using large-momentum effective theory (LaMET). The calculation is carried out on an ensemble with lattice spacing $a=0.098$ fm and pion mass $338$ MeV, at various proton momenta up to $2.11$ GeV. We have implemented perturbative matching up to the next-to-next-to-leading order together with a renormalization-group resummation improvement. The result exhibits a decay behavior with increasing transverse separation $b_\perp$. We also compare the results in the nucleon and pion.

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Lingquan Ma, Jun Hua, Andreas Schäfer, Hai-Tao Shu, Yushan Su, Peng Sun, Lisa Walter, Wei Wang, Xiaonu Xiong, Yi-Bo Yang, Jian-Hui Zhang, Qi-An Zhang. 2025-02-17. Quark Transverse Spin-Momentum Correlation of the Nucleon from Lattice QCD: The Boer-Mulders Function. https://arxiv.org/abs/2502.11807

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