Abstract
A single-spin asymmetry in the azimuthal distribution of neutral pions relative to the lepton scattering plane has been measured for the first time in deep-inelastic scattering of positrons off longitudinally polarized protons. The analyzing power in the moment of the cross section is This result is compared to single-spin asymmetries for charged pion production measured in the same kinematic range. The asymmetry is of the same size as the asymmetry and shows a similar dependence on the relevant kinematic variables. The asymmetry is described by a phenomenological calculation based on a fragmentation function that represents sensitivity to the transverse polarization of the struck quark.
- Received 4 April 2001
DOI:https://doi.org/10.1103/PhysRevD.64.097101
©2001 American Physical Society