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arXiv · 1909.08218

Towards a model independent extraction of the Boer-Mulders function

E. Christova·D. Kotlorz·E. Leader
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Abstract

At present, the Boer-Mulders function for a given quark flavour has been extracted from data on semi-inclusive deep inelastic scattering using the simplifying, but theoretically inconsistent, assumption that it is proportional to the Sivers function for each quark flavour. In this paper, using the latest semi-inclusive deep inelastic COMPASS deuteron data on the $\langle\cos\phi_h\rangle$ and $\langle\cos 2 \phi_h\rangle$ asymmetries we extract the collinear $x_B$-dependence of the Boer-Mulders function for the sum of the valence quarks $Q_V=u_V + d_V$ in an essentially model independent way, and find a significant disagreement with the published results. Our analysis also yields interesting information on the transverse momentum dependence of the unpolarized quark distribution and fragmentation functions.

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E. Christova, D. Kotlorz, E. Leader. 2019-09-18. Towards a model independent extraction of the Boer-Mulders function. https://arxiv.org/abs/1909.08218

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