Single spin asymmetries of inclusive hadrons produced in electron scattering from a transversely polarized 3 He target

Abstract

We report the first measurement of target single spin asymmetries (AN) in the inclusive hadron production reaction, e+3He↑→h+X, using a transversely polarized 3He target. The experiment was conducted at Jefferson Lab in Hall A using a 5.9-GeV electron beam. Three types of hadrons (π±, K±, and proton) were detected in the transverse hadron momentum range 0.54 <pT< 0.74 GeV/c. The range of xF for pions was -0.29 <xF< -0.23 and for kaons was -0.25 <xF< -0.18. The observed asymmetry strongly depends on the type of hadron. A positive asymmetry is observed for π+ and K+. A negative asymmetry is observed for π-. The magnitudes of the asymmetries follow |Aπ-|<|Aπ+|<|AK+|. The K- and proton asymmetries are consistent with zero within the experimental uncertainties. The π+ and π- asymmetries measured for the 3He target and extracted for neutrons are opposite in sign with a small increase observed as a function of pT. © 2014 American Physical Society.