Speaker
Description
The Heavy Photon Search (HPS) experiment searches for electro-produced dark photons using an electron beam provided by the CEBAF accelerator at the Thomas Jefferson National Accelerator Facility. A search for e+e- resonances in the invariant mass distribution has sensitivity to dark photons with larger coupling, while the additional requirement of a displaced vertex to identify long-lived dark photons adds sensitivity at smaller couplings beyond the reach of most other experiments. HPS employs a compact spectrometer, matched to the forward kinematic characteristics of A’ electro-production. The detector consists of a silicon tracker for momentum analysis and vertexing and a lead tungstate (PbWO4) electromagnetic calorimeter for particle ID and triggering. HPS completed a successful engineering run in 2015, collecting 1.7 days of data (10 mC) at 1.056 GeV beam energy, and again in 2016, collecting 5.4 days of data (92.5 mC) at 2.3 GeV beam energy. Results from the 2015 engineering run have demonstrated the full functionality of the experiment, while results from the 2016 dataset are nearing completion. Subsequent to 2016 operations, a small upgrade of the detector was completed in advance of a run in the summer/fall of 2019, collecting roughly two weeks of data at 4.55 GeV. The status of all ongoing analysis will be discussed, along with perspectives on the 2019 dataset and future operations.
