Study of Specific Properties of Hadrons via Precision Experiments at Jefferson Lab

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This research project is focused on two highly rated experimental projects at the Thomas Jefferson National Accelerator Facility in Virginia. One experiment will measure the proton radius, one of the most fundamental quantities in physics. It is directly related to the structure of the proton, which is a basic constituent block of visible matter. This research will continue the development and construction of a novel hydrogen target to perform a new electron-proton scattering experiment, directly giving the proton radius with higher precision. The second project will measure the lifetime of a particle called the eta meson with high precision, which will be compared with theoretical predictions from the fundamental theory of Quantum Chromodynamics (QCD). This project will also provide unique opportunities for students, both undergraduate and graduate, to be actively engaged in many different areas of interdisciplinary research: new hardware and cutting-edge software development; large scale data analysis and modern computational problems. In this way the research effort contributes to the development of a much-needed high tech workforce. As one of the most fundamental quantities in physics, the proton charge radius new independent measurement will have far reaching effect in both atomic and nuclear physics. The currently developed experimental situation with this quantity limits the determination of the Rydberg constant, one of the basic and the most precisely known constant in nature up to now. The experimental results may be sensitive to new physics beyond the Standard Model. The projected 3% accuracy of the eta-meson lifetime measurement will potentially resolve the long-standing discrepancy between the Primakoff-type and electron-positron collider experiments. It will also improve the light quark mass ratio in a direct and model independent way.