The Study of Wγ production at D0: Anomalous Coupling Limits and the Radiation Amplitude Zero

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W{gamma} production is analyzed in the electron and muon decay channels with approximately 1 fb{sup -1} of data from p{bar p} collisions that were produced at a center-of-mass energy of {radical}s = 1.96 TeV and that were collected by the D0 detector at the Fermilab Tevatron collider. The inclusive p{bar p} {yields} {ell}{nu}{gamma} cross section is measured in both channels and is found to be consistent with the Standard Model expectation of 2.08 {+-} 0.05{sub PDF} pb for events with a photon E{sub T} > 11 GeV, {Delta}R{sub {ell}{sub {gamma}}} > 0.7, and {ell}{nu}{gamma} transverse mass greater than 90 GeV . The observed cross section is measured to be 2.05 {+-} 0.18{sub stat} {+-} 0.10{sub sys} {+-} 0.13{sub lumi} pb and a.72 {+-} 0.19{sub stat} {+-} 0.15{sub sys} {+-} 0.10{sub lumi} pb for the electron and muon channels respectively. The photon E{sub T} spectrum is examined for indications of anomalous WW{gamma} couplings. No evidence is found, and the following one-dimensional limits are set at a 95% confidence level: -0.18 < {lambda} < 0.18 and 0.16 < {kappa} < 1.84. The observed charge-signed photon-lepton rapidity difference is consistent with the Standard Model prediction and is indicative of the theoretically expected radiationmore » amplitude zero. The distribution exhibits a bimodal structure which is expected from the destructive interference, with the unimodal hypothesis being ruled out at the 94% confidence level.« less