triplet of these Goldstones is eaten to become the longitudinal modes of the $W^{\pm}/Z^0$, while the other triplet remains in the spectrum. This remaining triplet, typically called the top-pions, and a singlet partner, the top-Higgs, are the focus of this paper.

The top-pions and top-Higgs couple preferentially to the third generation of quarks, which makes them interesting for a number of reasons. First, the interactions of the top quark are the least constrained of all fermions, so new dynamics coupling preferentially to the top quark is not phenomenologically excluded. Second, the gluon fusion mechanism involves a top quark loop and is an efficient method for singly producing top-Higgses and neutral top-pions at the LHC. In fact, the strong top-quark–topcolor interaction, manifest in a top Yukawa of order $\sim$ few, significantly enhances the coupling of top-Higgs and top-pions relative to a SM Higgs of equal mass . Such a large cross section leads to exciting LHC signals which may be discoverable in the initial low-energy, low-luminosity run.

Our goal in this paper is to lay the foundation for phenomenological studies of the top-pions and top-Higgs at the LHC. We begin in Sec. \[sec:model\] by setting out the relevant details of the 