Determination of the spin-dependent parton distributions in polarized leptoproduction of jets and heavy quarks

Charm leptoproduction asymmetries at Q2≅0 are estimated for forthcoming experiments with polarized lepton (e,μ) beams and polarized fixed targets. Recently proposed polarized gluon distributions ΔG(x,Q2) imply observable charm production asymmetries of about 30%. Other possible charm production asymmetry determinations, at higher values of Q2, as well as polarized deep inelastic large-kT jet production are furthermore critically considered for realistic experimental situations and appear to be unsuitable for extracting ΔG. (orig.)