Measurements with electroweak gauge bosons at LHCb

We have measured the W and Z boson production cross-sections in proton-proton collisions at a centre-of-mass energy of 7 TeV, using datasets of up to approximately 1 fb$^{-1}$ collected by the LHCb experiment. All measurements are based on boson decays with at least one lepton in the final state, which has transverse momentum $p_{T}$ exceeding 20~GeV and pseudorapidity $\eta$ within $2.0 - 4.5$. W bosons are reconstructed in decays to muons. Z bosons are reconstructed in decays to electron, muon or tau lepton pairs, where the reconstructed invariant mass $m_{Z}$ lies in the range $60 \leq m_{Z} \leq 120$~GeV. In all cases results are consistent with next-to-next-to-leading order perturbative QCD predictions.