Azimuthal single-spin asymmetries in semi-inclusive deep-inelastic   scattering on a transversely polarised hydrogen target
  Azimuthal single-spin asymmetries (SSA) in semi-inclusive electroproduction of charged pions and kaons in deep-inelastic scattering of positrons on a transversely polarised hydrogen target were observed. SSA amplitudes for both the Collins and the Sivers mechanism are presented. 
Markus Diefenthaler