We show in this work how a sub-100 GeV $Z$ in a $U(1)$ extension of the Standard Model (SM) can emerge through Higgs mediated channels at the Large Hadron Collider (LHC). The light $Z$ has minimal interaction with the SM sector as well as vanishing kinetic mixing with $Z$ boson which allows it to be light and below the SM gauge boson masses. Interestingly such a light $Z$ is very difficult to observe in the standard production modes. We show that it is possible to observe such a gauge boson via scalar mediators that are responsible for the symmetry breaking mechanism of the model. The model also provides a dark matter candidate whose compatibility with the observed relic density is established due to the light $Z$. We also comment on other interesting possibilities such a light $Z$ may present for other observables.
Download