On 15 September, the Thomas Jefferson National Accelerator Facility (Jefferson Lab) received approval from the US Department of Energy (DOE) to begin construction of a $310 million upgrade to the 12 GeV Continuous Electron Beam Accelerator Facility (CEBAF). The upgrade project has been a high priority for the DOE’s Office of Science since it published its landmark report, Facilities for the Future of Science: A Twenty Year Outlook, in 2003.
The construction approval, known as Critical Decision 3, concludes an exhaustive, multi-year review process that clearly established the scientific need, merit and quality of the 12 GeV CEBAF upgrade project that will see DOE’s Jefferson Lab double the energy of its accelerated electron beam from 6 GeV to 12 GeV.
It will also construct a new experimental hall and upgrade the equipment in its three existing experimental halls. Construction funds are requested in the US president’s fiscal year 2009 budget request and project completion is planned for 2015.
With the upgrade, researchers at Jefferson Lab plan to investigate quark confinement further and to map in detail the distributions of quarks in space and momentum, culminating in measurements that will provide a 3D picture of the internal structures of protons and neutrons. They also plan to study the role of quarks in the structure and properties of atomic nuclei, as well as how these quarks interact with a dense nuclear medium. Once completed, the upgraded facility will allow studies of the limits of the Standard Model.