During the award period, the Arizona State University Meson Physics Group will continue to study the internal quark structure of the neutrons and protons (nucleons) that make up atomic nuclei. The group will use high energy photons to excite these neutrons and protons, and then study the ways these excited nucleons decay. In particular, we will look for the emission of eta and eta-mesons during the decay process. By observing various decay modes, we will provide important data that will test and refine theories of how the neutrons and protons are built up from quarks.
The high energy photons will be provided by the Bremsstrahlung Photon Tagging Facility in Experimental Hall B at the Thomas Jefferson National Accelerator Facility in Newport News, Virginia. The decay products will be studied using the CEBAF Large Acceptance Spectrometer (CLAS) in Hall B. Members of the ASU Meson Physics Group form part of the CLAS Collaboration and, during the award period, we will provide service work associated with maintaining this experimental equipment, as well as support data-taking for CLAS experiments as required.
