Support from this grant will be used to continue a program of nuclear physics research focused on the fundamental properties of the nucleon. The program is based at the Thomas Jefferson National Accelerator Facility (JLab) and is focused on two objectives. The primary goal of this program will be to complete the construction of a tracking system for the Qweak experiment with the involvment of two students. The second objective will be to prepare a physics program as well as design and construct instrumentation for the JLab 12 GeV upgrade. The Qweak experiment is a parity-violating electron scattering experiment designed to measure the weak charge of the proton. A measurement of the proton's weak charge can be used to extract a fundamental quantity known as the weak mixing angle. The current description of particle interactions, commonly referred to as the ""Standard Model"", predicts how the weak mixing angle changes with the amount of momentum that is transferred during an interaction. As a result, a measurement of the proton's weak charge will evaluate the veracity of the Standard Model as well as be sensitive to competing theoretical descriptions involving new physics should the Standard Model fall short.
While this NSF-supported program will primarily construct a tracking system critical to the Qweak experiment, it will also continue to play a major role developing a physics program and instrumentation for the JLab 12 GeV upgrade. The principal investigator is a co-spokesperson for a physics program to measure polarization observables of the nucleon at an energy upgraded JLab. The measurements made will constrain the stark theoretical predictions describing these distributions at kinematic regions where the probed quark carries most of the nucleons momentum. The PI is also supervising the design of a tracking system for the JLab energy upgrade. The development of particle tracking systems for Qweak and the JLab 12 GeV upgrade is the means through which this program educates both graduate and undergraduate students thereby enhancing the intellectual infrastructure of our technology driven society.
