A strategy for the analysis of semi-inclusive deep inelastic scattering

We present a strategy for the systematic extraction of a vast amount of det ailed information on polarized parton densities and fragmentation functions from semi-inclusive deep inelastic scattering l + N --> l + h + X, in both LO and NLO QCD. A method is suggested for estimating the errors involved i n the much simpler, and therefore much more attractive, LO analysis. The ap proach is based upon a novel interplay with data from inclusive DIS and fro m e(+)e(-) --> hX, and leads to a much simplified form of the NLO expressio ns. No assumptions are made about the equality of any parton densities and the only symmetries utilised are charge conjugation invariance and isotopic spin invariance of strong interactions. (C) 2001 Elsevier Science B.V. All rights reserved.