Search for Charged Higgs Bosons through Vector-Like Top Quark Pair Production at the LHC

We investigate the production and decay of a vector-like top partner (T) with charge 2/3 within the Two Higgs Doublet Model Type II (2HDM-II) extended by a vector-like quark (VLQ) doublet ($TB$). This study focuses on the decay sequence where the T quark produces a charged Higgs boson (H⁺) and a bottom quark, followed by the H⁺ decay into a top and bottom quark, due to the small branching ratio for H⁺ → τν in the studied region. Previous research {https://doi.org/10.1103/PhysRevD.109.055016}{[Phys.Rev.D109,055016]} has shown that the decay pathway T → H⁺b followed by H⁺ → tb is dominant across a significant portion of the parameter space. We analyze the collider process pp → TT̄ → (bH⁺)(b̄H⁻) → (b(tb))(b̄(t̄b)), resulting in final states enriched with bottom quarks. Our findings highlight this channel as a promising avenue for discovering the new top partner and charged Higgs boson, offering substantial detection potential across a broad parameter space.