2024/07/01 by Arhrib, Abdesslam, Benbrik, Rachid, Berrouj, Mbark +2
#FOS: Physical sciences #High Energy Physics - Phenomenology (hep-ph)
paper · doi:10.48550/arxiv.2407.01348
We investigate the discovery prospects for a vector-like top partner (VLT) in the Type-II Two-Higgs-Doublet Model (2HDM-II) extended by a vector-like quark doublet (TB) at the 14~TeV LHC. The study focuses on the pair production process pp → TT → bH+ bH- → b(tb) b(tb), yielding fully hadronic final states characterized by high b-jet multiplicity. Two analysis strategies are employed, requiring at least four or five b-tagged jets (4b and 5b), to exploit the signal topology. Assuming a charged Higgs mass of mH^± ∼ 600~GeV and a systematic uncertainty of δ= 5%, the 4b channel enables discovery up to mT ∼ 1200~GeV at L = 300~fb-1, while the 5b analysis extends the reach to mT ∼ 1300~GeV. At higher luminosities of 1000--3000~fb-1, the 5b strategy achieves discovery sensitivity up to mT ∼ 1400~GeV. The reach is significantly reduced as mH^± increases, due to the suppression of the BR(T → H+ b): for mH^± ∼ 1000~GeV, discovery becomes unattainable across all luminosity and systematic uncertainty configurations. Sensitivity is also strongly impacted by systematic uncertainties: for δ= 10% and mH^± < 1000~GeV, discovery remains viable up to mT ∼ 1200~GeV in the 5b analysis, while for δ= 20%, no discovery is achievable for mT ≥ 1000~GeV.