Studies of single-spin and double-spin asymmetries in pions electroproduction in semi-inclusive deep-inelastic scattering of 5.776GeV polarized electrons from unpolarized and polarized targets at the Thomas Jefferson National Accelerator Facility, are presented. The dependence of these amplitudes on Bjorken x and on the pion transverse momentum has been extracted with significantly higher
precision than previous data and is compared to model calculations
