  A search for resonant diboson production using a data sample corresponding to
4.7 fb-1 of integrated luminosity collected by the ATLAS experiment at the
Large Hadron Collider in pp collisions at 7 TeV is presented. The search for a
narrow resonance in the WW or WZ mass distribution is conducted in a final
state with an electron or a muon, missing transverse momentum and at least two
jets. No significant excess is observed and limits are set using three
benchmark models: WW resonance masses below 940 GeV and 710 GeV are excluded at
95% confidence level for spin-2 Randall-Sundrum and bulk Randall-Sundrum
gravitons, respectively; WZ resonance masses below 950 GeV are excluded at 95%
confidence level for a spin-1 Extended Gauge Model W' boson.
