Single Spin Asymmetries of Inclusive Hadrons Produced in Electron Scattering from a Transversely Polarized ${}^3$He Target

We report the first measurement of target single-spin asymmetries (A${}_N$) in the inclusive hadron production reaction, $e$+${}^3{\text{He}}^{\uparrow }\to h+X$, using a transversely polarized ${}^3$He target. The experiment was conducted at Jefferson Lab in Hall A using a 5.9-GeV electron beam. Three types of hadrons (${\pi }^{\pm }$, ${\text{K}}^{\pm }$ and proton) were detected in the transverse hadron momentum range 0.54 $<p_T<$ 0.74 GeV/c. The range of $x_F$ for pions was -0.29 $<x_F<$ -0.23 and for kaons -0.25 $<x_F<$-0.18. The observed asymmetry strongly depends on the type of hadron. A positive asymmetry is observed for ${\pi }^{+}$ and ${\text{K}}^{+}$. A negative asymmetry is observed for ${\pi }^{-}$. The magnitudes of the asymmetries follow $\mathrm{\mid }{A}^{{\pi }^{-}}\mathrm{\mid }<\mathrm{\mid }{A}^{{\pi }^{+}}\mathrm{\mid }<\mathrm{\mid }{A}^{K^{+}}\mathrm{\mid }$. The K${}^{-}$ and proton asymmetries are consistent with zero within the experimental uncertainties. The ${\pi }^{+}$ and ${\pi }^{-}$ asymmetries measured for the ${}^3$He target and extracted for neutrons are opposite in sign with a small increase observed as a function of $p_T$.