Pair production of the singlet vector-like B quark at the CLIC

Abstract

Vector-like quarks (VLQs) are a common feature of many scenarios of new physics beyond the Standard Model (SM), which generally decay into a SM third-generation quark with a SM gauge boson or a Higgs boson. The presence of a new exotic decay mode of VLQs will reduce the branching ratios of these standard decay modes and thus relax the current mass exclusion limits from LHC experiments. Based on a model-independent framework, we investigate the prospect of discovering the pair production of the weak-singlet VLQ-B at the future 3-TeV Compact Linear Collider (CLIC), by focusing on the final states including one Z boson and four b-jets via two types of modes: $$Z\rightarrow \ell ^{+}\ell ^{-}$$ Z → ℓ + ℓ - and $$Z\rightarrow \nu {\bar{\nu }}$$ Z → ν ν ¯ . By performing a rapid detector simulation of the signal and background events, and considering the initial state radiation and beamstrahlung effects, the exclusion limit at the 95% confidence level and the $$5\sigma $$ 5 σ discovery prospects are respectively obtained on the branching ratio of $$B\rightarrow bZ$$ B → b Z and the VLQ-B masses at the future 3-TeV CLIC with an integrated luminosity of 5 ab$$^{-1}$$ - 1 .

Search for an exotic vectorlike X-quark in same-sign dilepton final states at the future 3 TeV CLIC*

“…[49][50][51][52][53][54][55][56], the cross sections of single production processes for various types of VLQs are very sensitive to the EW coupling parameter. However, the cross sections for pair production processes only depend on the mass of VLQs for a given center-of-mass energy [57,58]. A unique signature of VLQ-X is the inclusion of SSDL, which arises from the decay channel with the leptonic decay of the W boson.…”