Quark helicity distributions from longitudinal spin asymmetries in muon-proton and muon-deuteron scattering

  title={Quark helicity distributions from longitudinal spin asymmetries in muon-proton and muon-deuteron scattering},
  author={Compass Collaboration},
Double-spin asymmetries for production of charged pions an d kaons in semi-inclusive deep-inelastic muon scattering have been measured by the COMPASS experimen t at CERN. The data, obtained by scattering a 160 GeV muon beam off a longitudinally polari sed NH3 target, cover a range of the Bjorken variablex between 0.004 and 0.7. A leading order evaluation of the heli city distributions for the three lightest quarks and antiquark flavours derived from these asymmetries and from our previous… Expand

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