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

We present a search for the technicolor particles 𝜌𝑇 and 𝜋𝑇 in the process 𝑝⁢ ‾‾‾ 𝑝 →𝜌𝑇 →𝑊⁢𝜋𝑇 at a center of mass energy of √𝑠 =1.96  TeV . The search uses a data sample corresponding to approximately 1.9  fb−1 of integrated luminosity accumulated by the CDF II detector at the Fermilab Tevatron. The event signature we consider is 𝑊 →ℓ⁢𝜈 and 𝜋𝑇 →𝑏⁢ ‾‾‾ 𝑏 , 𝑏⁢ ‾ 𝑐 or 𝑏⁢ ‾‾‾ 𝑢 depending on the 𝜋𝑇 charge. We select events with a single high-𝑝𝑇 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 𝜌𝑇−𝜋𝑇 mass plane. As a result, a large fraction of the region 𝑚⁡(𝜌𝑇) =180–250  GeV/𝑐2 and 𝑚⁡(𝜋𝑇) =95–145  GeV/𝑐2 is excluded.