Probing the Scale of New Physics in the $ZZ\gamma$ Coupling at $e^{+}{e}^{-}$ Colliders

John Ellis, Shao-Feng Ge, Hong-Jian He +1

The $ZZ\gamma$ triple neutral gauge couplings are absent in the Standard Model (SM) at the tree level. They receive no contributions from dimension-6 effective operators, but can arise…