Journal Article URL
Physical Review C
We report the first measurement of target single spin asymmetries of charged kaons produced in semi-inclusive deep inelastic scattering of electrons off a transversely polarized He-3 target. Both the Collins and Sivers moments, which are related to the nucleon transversity and Sivers distributions, respectively, are extracted over the kinematic range of 0.1 < x(bj) < 0.4 for K+ and K- production. While the Collins and Sivers moments for K+ are consistent with zero within the experimental uncertainties, both moments for K- favor negative values. The Sivers moments are compared to the theoretical prediction from a phenomenological fit to the world data. While the K+ Sivers moments are consistent with the prediction, the K- results differ from the prediction at the 2-sigma level.
Zhao, Y. X., Wang, Y., Allada, K., Aniol, K., Annand, J. R. M., Averett, T., ... & Camsonne, A. (2014). Single spin asymmetries in charged kaon production from semi-inclusive deep inelastic scattering on a transversely polarized He 3 target. Physical Review C, 90(5), 055201.