An experiment to measure single-spin asymmetries in semi-inclusive production
of charged pions in deep-inelastic scattering on a transversely polarized
3He target was performed at Jefferson Lab in the kinematic region of
0.16<x<0.35 and 1.4<Q2<2.7GeV2. The pretzelosity asymmetries on
3He, which can be expressed as the convolution of the h1T⊥
transverse momentum dependent distribution functions and the Collins
fragmentation functions in the leading order, were measured for the first time.
Using the effective polarization approximation, we extracted the corresponding
neutron asymmetries from the measured 3He asymmetries and cross-section
ratios between the proton and 3He. Our results show that for both
π± on 3He and on the neutron the pretzelosity asymmetries are
consistent with zero within experimental uncertainties.Comment: 6 pages, 3 figures; enlarged the legends in Fig.3; added 3 citation