Testing the Technicolor Interpretation of the CDF Dijet Excess at the 8-TeV LHC

TL;DR

This paper investigates the potential to confirm the technicolor explanation for the CDF dijet excess at the 8-TeV LHC by proposing specific kinematic tests and search channels, emphasizing the importance of certain decay modes for validation.

Contribution

It introduces tailored cuts and new kinematic tests at the LHC to confirm the technicolor hypothesis for the CDF excess, focusing on specific decay channels and their expected rates.

Findings

Certain cuts used by CDF and ATLAS cannot confirm the signal.

Proposed cuts at the LHC may reveal $ ho_T ightarrow ext{lepton} u jj$.

The $Z ext{--} ext{pi}_T$ channel is cleaner and can be discovered or excluded by 2012.

Abstract

Under the assumption that the dijet excess seen by the CDF Collaboration near 150 Gev in Wjj production is due to the lightest technipion of the low-scale technicolor process $\rho_T \rightarrow W \pi_T$, we study its observability in LHC detectors for 8 TeV collisions and 20 inverse femtobarns of integrated luminosity. We describe interesting new kinematic tests that can provide independent confirmation of this LSTC hypothesis. We show that cuts similar to those employed by CDF, and recently by ATLAS, cannot confirm the dijet signal. We propose cuts tailored to the LSTC hypothesis and its backgrounds at the LHC that may reveal $\rho_T \rightarrow \ell\nu jj$. Observation of the isospin-related channel $\rho^{\pm}_T \rightarrow Z \pi^{\pm}_T \rightarrow \ell^+\ell^- jj$ and of $\rho^{\pm}_T \rightarrow WZ$ in the $\ell^+\ell^-\ell^{pm}\nu_\ell$ and $\ell^+\ell^- jj$ modes will be important confirmations of the LSTC interpretation of the CDF signal. The $Z\pi_T$ channel is experimentally cleaner than $W\pi_T$ and its rate is known from $W\pi_T$ by phase space. It can be discovered or excluded with the collider data expected by the end of 2012. The $WZ \rightarrow 3\ell\nu$ channel is cleanest of all and its rate is determined from $W\pi_T$ and the LSTC parameter $\sin\chi$. This channel and $WZ \to \ell^+\ell^- jj$ are discussed as a function of $\sin\chi$.