Longitudinal polarization of $\Lambda$ and $\bar\Lambda$ in   deep-inelastic scattering at COMPASS
  Production of $\Lambda$ and $\bar\Lambda$ hyperons in deep-inelastic scattering of 160 GeV/c polarized muons is under study in the COMPASS (CERN NA58) experiment. Preliminary results on longitudinal polarization of the hyperons from the data collected during the 2002 run are presented. 
M.G.Sapozhnikov (on behalf of the COMPASS Collaboration)