Search for Technicolor Particles Produced in Association with a W Boson at CDF

We present a search for the technicolor particles rho(T) and pi(T) in the process p (p) over bar-> rho(T)-> Wpi(T) at a center of mass energy of root s=1.96TeV. The search uses a data sample corresponding to approximately 1.91 fb(-1) of integrated luminosity accumulated by the CDF II detector at the Fermilab Tevatron. The event signature we consider is W->lnu and pi(T)->b (b)over bar, b(c)over bar or b (u) over bar depending on the pi(T) charge. We select events with a single high-p(T) electron or muon, large missing transverse energy, and two jets. Jets corresponding to bottom quarks are identified with multiple b-tagging algorithms. The observed number of events and the invariant mass distributions are consistent with the standard model background expectations, and we exclude a region at 95% confidence level in the rho(T)-pi(T) mass plane. As a result, a large fraction of the region m(rho(T))=180-250 GeV/c2 and m(pi(T))=95-145 GeV/c(2) is excluded.