Studies of final-state photon radiation and mixed EW + QCD higher-order corrections in the process $p\,p,\,p\bar{p}\rightarrow W^\pm \rightarrow \ell^\pm\nu$

Work has been done to extend the Monte Carlo program WGRAD2$^{12}$, which includes the complete ${\cal O}(\alpha)$ electroweak (EW) radiative corrections to $p\,p,\,p\bar{p}\rightarrow W^\pm \rightarrow \ell^\pm\nu$ to include multiple, soft, final-state photon radiation (mFSR) from a final state lepton as well as initial state QCD corrections up to ${\cal O}(\alpha_s)$. Final state multiple photon radiation is implemented via the QED structure function approach. In this way we study the combined effects of EW and QCD higher-order corrections to this process. In addition to mFSR and QCD NLO corrections, we discuss plans to model initial-state parton shower effects using the POWHEG$^3$ parton shower generator. With WGRAD3 one could then study effects on the W boson mass and other observables due to mixed EW + QCD corrections up to NNLO, initial-state parton showering and final-state multiple, soft photon radiation. \vspace{.53em}\\ $^1$U.Baur, S.Keller, D.Wackeroth, Phys. Rev. D59, 013002 (1999)\\ $^2$U.Baur, D.Wackeroth, Phys. Rev. D70, 073015 (2004)\\ $^3$P.Nason, JHEP 0411 (2004) 040, [arXiv:hep-ph/0409146]