Single target-spin asymmetries in semi-inclusive pion electroproduction on longitudinally polarized protons

Abstract

We evaluate the single target-spin sin(phi_h) and sin(2φ_h) azimuthal asymmetries in the semi-inclusive deep inelastic lepton scattering off longitudinally polarized proton target under HERMES kinematic conditions. A good agreement with the HERMES data can be achieved using only the twist-2 distribution and fragmentation functions.

Figures (3)

• Figure 1: The definition of the azimuthal angle $\phi_h$ and the target polarization components in virtual photon frame.
• Figure 2: The $A^{\sin\phi_h}_{UL}(x)$ asymmetry of $\pi^{\pm}$ production. The continuous ($\pi^{+}$) and dashed ($\pi^{-}$) curves correspond to $M_C=0.7$ GeV, $h_1=g_1$; dotted ($\pi^{+}$) and dot-dashed ($\pi^{+}$) to $M_C=0.3$ GeV, $h_1=g_1$ and $M_C=0.7$GeV $h_1=(f_1+g_1)/2$, respectively.
• Figure 3: The ratio of the amplitudes of the $\sin2\phi_h$ and $\sin\phi_h$ single target-spin asymmetries for $\pi^{+}$ production. The curves have the same notations as in the Fig. \ref{['fig:f1']}.