Technicolor in the LHC Era

TL;DR

This paper discusses how LHC searches for Higgs bosons constrain technicolor models, especially technipions, by analyzing their production and decay signatures in light of recent experimental results.

Contribution

It provides updated constraints on technicolor models with colored technifermions based on LHC Higgs search data, excluding certain technipion mass ranges.

Findings

Technipions with masses from 110 GeV to nearly 2m_t are excluded.

Enhanced production and decay rates of technipions are constrained by LHC data.

Models with N_{TC} > 3 and topcolor dynamics face strong experimental limits.

Abstract

LHC searches for the standard model Higgs Boson in \gamma\gamma\ or \tau\tau\ decay modes place strong constraints on the light technipion state predicted in technicolor models that include colored technifermions. Compared with the standard Higgs Boson, the technipions have an enhanced production rate (largely because the technipion decay constant is smaller than the weak scale) and also enhanced branching ratios into di-photon and di-tau final states (largely due to the suppression of WW decays of the technipions). Recent ATLAS and CMS searches for Higgs bosons exclude the presence of technipions with masses from 110 GeV to nearly 2m_t in technicolor models that (a) include colored technifermions (b) feature topcolor dynamics and (c) have technicolor groups with three or more technicolors (N_{TC} > 3).