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 ${}^3\mathrm{He}$ 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.

• Received 28 April 2014

DOI:https://doi.org/10.1103/PhysRevC.90.055201