text: Dr. Charles D. Ellis is currently a Research Instructor at the Vanderbilt University School of Medicine in Nashville, Tennessee. Dr. Ellis received his doctorate in Inorganic Chemistry from the University of North Carolina at Chapel Hill, and began his career at E. I. du Pont de Nemours & Co., where he received a US Patent for medical X-ray film technology. He started his academic career at Vanderbilt in the Center for Structural Biology, where he performed research on the expression and structural determination of membrane proteins. He co-authored a paper that describes the NMR structure determination of an integral membrane protein enzyme, diacylglycerol kinase, a 100-kDa protein-detergent complex, which was published in Science. Dr. Ellis has since joined the Division of Nephrology where he manages all facets of the clinical, translational and epidemiological research activities for a number of senior and junior faculty. His areas of expertise include (1) regulatory (Institutional Review Boards, Data Safety Monitoring Boards, ClinicalTrials.gov listings); (2) financial (budget development and analysis, Billing Plan/FACTr submissions, billing/invoicing, contracts); (3) database creation and management (both REDCap and Access-based); (4) data and trial coordination (Investigational Drug Services, Data Coordinating Centers, equipment, personnel); and (5) operational (standard operating procedures, sample collection/processing/analysis).
  
  The Heavy Photon Search (HPS), an experiment to search for a hidden sector photon in fixed target electroproduction, is preparing for installation at the Thomas Jefferson National Accelerator Facility (JLab) in the Fall of 2014. As the first stage of this project, the HPS Test Run apparatus was constructed and operated in 2012 to demonstrate the experiment's technical feasibility and to confirm that the trigger rates and occupancies are as expected. This paper describes the HPS Test Run apparatus and readout electronics and its performance. In this setting, a heavy photon can be identified as a narrow peak in the e$^+$e$^-$ invariant mass spectrum, above the trident background or as a narrow invariant mass peak with a decay vertex displaced from the production target, so charged particle tracking and vertexing are needed for its detection. In the HPS Test Run, charged particles are measured with a compact forward silicon microstrip tracker inside a dipole magnet. Electromagnetic showers are detected in a PbW0$_{4}$ crystal calorimeter situated behind the magnet, and are used to trigger the experiment and identify electrons and positrons. Both detectors are placed close to the beam line and split top-bottom. This arrangement provides sensitivity to low-mass heavy photons, allows clear passage of the unscattered beam, and avoids the spray of degraded electrons coming from the target. The discrimination between prompt and displaced e$^+$e$^-$ pairs requires the first layer of silicon sensors be placed only 10~cm downstream of the target. The expected signal is small, and the trident background huge, so the experiment requires very large statistics. Accordingly, the HPS Test Run utilizes high-rate readout and data acquisition electronics and a fast trigger to exploit the essentially 100% duty cycle of the CEBAF accelerator at JLab.
  The focusing strength of plasma lenses used with high energy electron or positron beams can give rise to synchrotron radiation with critical energies in the MeV range. A method is described for measuring the characteristic energy of this radiation as a way of monitoring the strength of the focus. The principle has been implemented in a plasma lens experiment with a 28.5 GeV positron beam.