  Cross sections for e-p charged current deep inelastic scattering have been
measured at a centre-of-mass energy of 318 GeV with an integrated luminosity of
16.4 pb-1 using the ZEUS detector at HERA. Differential cross-sections
d\sigma/dQ2, d\sigma/dx and d\sigma/dy are presented for Q2>200 GeV2. In
addition, d2\sigma/dxdQ2 was measured in the kinematic range 280 GeV2 < Q2 <
30000 GeV2 and 0.015 < x < 0.42. The predictions of the Standard Model agree
well with the measured cross sections. The mass of the W boson, determined from
a fit to d\sigma/dQ2, is MW=80.3 \pm 2.1 (stat.) \pm 1.2 (syst.) \pm 1.0 (PDF)
GeV.
