Oct 2023 - Sep 2024

Mixing and Oscillations in Nearly Degenerate Vector Bosons

by Prisco Lo Chiatto (Mainz)




We extend the phenomenology of mixing and oscillation to U (1) vector bosons. Extracting constraints on kinetic mixing between a new U (1)′ gauge boson hiding under the Standard Model Z boson resonance requires the formalism of non-Hermitian two-point correlation functions at 1-loop order, whose phenomenology is reminiscent of neutral kaons in the SM. After updating the collider constraints on Z′ bosons with kinetic mixing in the narrow mass window around the Z boson, we discuss the novel phenomenology of Z′ regeneration and motivate searches for displaced vertices from Z′ decays. The time evolution of the highly mixed state also exhibits the quantum Zeno phenomenon.