Longitudinal structure functions in high-energy lepton-hadron scattering

The ratio of longitudinal to transverse structure functions at high energies, hitherto unmeasured, can be determined from the present generation of muon-hadron scattering experiments. This quantity has an important bearing on the viability of the quark-parton picture and the correct interpretation of the "anomalies" of high-energy neutrino and antineutrino scattering experiments.