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arXiv · 0705.1573

Are all Boer-Mulders functions alike?

Matthias Burkardt·Brian Hannafious
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Abstract

Chirally odd generalized parton distributions (GPDs) and the Boer-Mulders function provide valuable information about spin-orbit correlations for quarks in nucleons and other hadrons. We compare results for the relevant GPD $\bar{E}^q_T$ from a variety of phenomenological models as well as recent lattice results. We find that $\bar{E}^q_T>0$ for nucleons as well as the pion and for both $u$ and $d$ quark. As a result, the corresponding Boer Mulders functions are all expected to be negative. The sign of $\bar{E}^q_T$ arises from the relative sign between the upper and lower Dirac components for the quark wave functions.

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Matthias Burkardt, Brian Hannafious. 2007-05-13. Are all Boer-Mulders functions alike?. https://doi.org/10.1016/j.physletb.2007.09.064

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