The Heavy Photon Search Experiment at Jefferson Lab

The Heavy Photon Search (HPS) is a new experiment at Jefferson Lab that will search for massive U(1) vector bosons (also known as heavy photons, dark photons, or $A'$) of mass 20--1000 MeV that couple to electric charge with relative coupling $\alpha'/\alpha$ of $10^{-5}$--$10^{-10}$. The HPS experiment is designed to produce heavy photons by electron scattering off a fixed target, and detect decays to $e^+e^-$ pairs with two signatures (invariant mass resonance and displaced decay vertex). The detector is a compact, large-acceptance forward spectrometer comprising a silicon microstrip tracker for momentum measurement and vertexing and an electromagnetic calorimeter for triggering on $e^+e^-$. This talk will give an overview of the HPS experiment and its current status after test, commissioning, and engineering runs.