First study of the radiation-amplitude zero in Wgamma production and limits on anomalous WWgamma couplings at sqrt[s]=1.96 TeV

Phys Rev Lett. 2008 Jun 20;100(24):241805. doi: 10.1103/PhysRevLett.100.241805. Epub 2008 Jun 20.

Abstract

We present results from a study of pp-->Wgamma+X events utilizing data corresponding to 0.7 fb{-1} of integrated luminosity at sqrt[s]=1.96 TeV collected by the D0 detector at the Fermilab Tevatron Collider. We set limits on anomalous WWgamma couplings at the 95% C.L. The one-dimensional 95% C.L. limits are 0.49<kappa{gamma}<1.51 and -0.12<lambda{gamma}<0.13. We make the first study of the charge-signed rapidity difference between the lepton and the photon and find it to be indicative of the standard model radiation-amplitude zero in the Wgamma system.