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

TL;DR

This paper reports a search for technicolor particles produced with a W boson at the Fermilab Tevatron, setting exclusion limits on their masses based on data from the CDF II detector.

Contribution

The study provides the first search for technicolor particles in association with a W boson at Tevatron energies, establishing new exclusion limits in the mass plane.

Findings

No significant excess over standard model background observed.

Excluded a large region of the $ ho_T$ and $ ho_T$-$ ho_T$ mass plane.

Set 95% confidence level exclusion limits on technicolor particle masses.

Abstract

We present a search for the technicolor particles $\rho_{T}$ and $\pi_{T}$ in the process $p\bar{p} \to \rho_{T} \to W\pi_{T}$ at a center of mass energy of $\sqrt{s}=1.96 \mathrm{TeV}$. The search uses a data sample corresponding to approximately $1.9 \mathrm{fb}^{-1}$ of integrated luminosity accumulated by the CDF II detector at the Fermilab Tevatron. The event signature we consider is $W\to \ell\nu$ and $\pi_{T} \to b\bar{b}, b\bar{c}$ or $b\bar{u}$ 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 $m(\rho_T) = 180$ - $250 \mathrm{GeV}/c^2$ and $m(\pi_T) = 95$ - $145 \mathrm{GeV}/c^2$ is excluded.