The Boer-Mulders Function: Models and Universality

Understand

The sign of the Boer-Mulders function $h_1^\perp$ is related to the sign of the GPD $\bar{E}_T$ through the mechanism of chromodynamic lensing.

• Model calculations of the sign of $\bar{E}_T$ indicate that the sign of $h_1^\perp$ may be the same in all ground state hadrons.