Beam spin asymmetry of neutral pion in semi-inclusive electroproduction

Abstract

We study the beam spin asymmetry A sin φh LU in semi-inclusive electroproduction of neutral pion contributed by the T -odd twist-3 distribution function g ⊥ (x, k 2). The distributions for the u and d quarks inside the proton are calculated in a spectator model including the scalar and the axialvector diquark components. Using the model results, we estimate the asymmetry A sin φh LU in ep→ e ′ π 0 X process in which the lepton beam is longitudinally polarized. The model prediction is compared with the data measured by the CLAS and HERMES Collaborations, showing that our numerical results agree with the experimental data reasonably. We also make a prediction on the beam spin asymmetry in π 0 electroproduction at CLAS12 using the same model calculation.