Searching for a vector-like B quark through a tW decay channel at future electron–positron colliders

Abstract

Vector-like quarks are predicted by several theoretical scenarios of new physics which could solve the hierarchy problem in particular and might be produced through electroweak interactions. In this work, we investigate the prospects for discovering the SU(2) singlet vector-like bottom quark (VLQ-B) in $$e^{+}e^{-}$$ e + e - collisions at the future proposed 3 TeV Compact Linear Collider (CLIC). The analysis is performed within the framework of a simplified model featuring only two free parameters: the VLQ-B mass $$m_B$$ m B and the coupling constant $$g^{*}$$ g ∗ . We study its single production process $$e^{+}e^{-}\rightarrow B{\bar{b}}$$ e + e - → B b ¯ and perform a detailed analysis in the decay channel $$B\rightarrow tW^{-}$$ B → t W - at the 3 TeV CLIC. The $$2\sigma $$ 2 σ exclusion limit and $$5\sigma $$ 5 σ discovery prospects are obtained for the model parameters, respectively. Our results show that the future CLIC will be an ideal hunting ground for such vector-like quarks which have electroweak interactions.

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

“…As shown in Refs. [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].…”