Abstract: | The ZEUS inclusive differential cross-section data from HERA, for charged and neutral current processes taken with e + and e- beams, together with differential cross-section data on inclusive jet production in e + p scattering and dijet production in scattering, have been used in a new NLO QCD analysis to extract the parton distribution functions of the proton. The input of jet-production data constrains the gluon and allows an accurate extraction of at NLO; An additional uncertainty from the choice of scales is estimated as . This is the first extraction of from HERA data alone. |