NEW MEASUREMENTS OF PROTON POLARIZED STRUCTURE FUNCTIONS IN CHARGED CURRENT PROCESSES AT DESY HERA

Predictions for longitudinal spin asymmetries which single out new pol arized nucleon structure functions in deeply inelastic charged current interactions at DESY HERA energies are given, exploiting their interp retation in terms of polarized quark distributions. These asymmetries turn out to be large and allow a measurement of the new polarized stru cture functions g(1)(W) and g(5)(W), which would add valuable tests an d information on the spin content of quarks inside a polarized proton. We also show that single-spin asymmetries in neutral current interact ions are very small.