Single production of dark photon at the LHC

Many extensions of the SM contain hidden sectors which are uncharged under the SM gauge group. The simplest model with an additional $U(1)$ group predicts the existence of the new gauge boson, dark photon $Z_D$. In this work we consider single production of dark photon $Z_D$ at the LHC and study its discovery potential via the process $pp\rightarrow Z_D\gamma\rightarrow ll\gamma$. After simulating the signal as well as the relevant backgrounds, the numerical results show that the signal of $Z_D$ might be detected at the 14TeV LHC.