Combined electroweak and QCD fits including NC and CC data with polarized electron beam at HERA-2

Abstract : A combined electroweak and QCD analysis is performed to determine electroweak parameters accounting for their correlation with parton distributions. The analysis is based on the deep inelastic e^+p and e^−p charged and neutral current scattering cross sections measured by the H1 experiment, including data with polarised lepton beams. The precision has been improved in particular for u quark coupling to the Z^0 boson with respect to the published results based on the unpolarised HERA data only. The determinations from HERA are compared with those from LEP and Tevatron.