Vector-like tops from first generation quarks: the role of width and coupling chiralities in same-charge production at the LHC

Abstract

In this paper, we tension the scope of the $q\bar q, gg\to T \bar T$ production process against that of the same-charge $uu\to TT$ one in searching for Vector-Like Quarks (VLQs) with electromagnetic charge $+2/3$ at the Large Hadron Collider (LHC). The study is conducted by considering a simplified model in which such new states couple exclusively to Standard Model quarks of the first generation through $W^\pm, Z$ and $H$ currents. We consider both left-handed or right-handed dominant chiralities, representative of $SU(2)_L$ singlets or doublets, and the total widths are allowed to reach large values relatively to the VLQ masses. By deconstructing the signal into all its components, we assess current and projected constraints, emphasize the role of interference terms and isolate peculiar features which can be used for dedicated searches at the LHC or future colliders.