Search for sterile neutrino with light gauge interactions: recasting collider, beam-dump, and neutrino telescope searches

We investigate features of the sterile neutrinos in the presence of a light gauge boson $X^mu$ that couples to the neutrino sector. The novel bounds on the active-sterile neutrino mixings $| U_{ell 4} |^2$, especially for tau flavor ($l = tau$), from various collider and fixed target experiments are explored. Also, taking into account the additional decay channel of the sterile neutrino into a light gauge boson ($ u_4 to u_ell e^+ e^-$), we explore and constrain a parameter space for low energy excess in neutrino oscillation experiments.