The U.S. Department of Energy's Thomas Jefferson National Accelerator Facility (Jefferson Lab) today received approval from DOE to begin construction on a $310 million project that will provide physicists worldwide with an unprecedented ability to study the basic building blocks of the visible universe.
The 12 GeV Continuous Electron Beam Accelerator Facility (CEBAF) upgrade project has been a high priority for DOE's Office of Science since it published its landmark report, "Facilities for the Future of Science: A Twenty Year Outlook" in 2003. The report was the first long-range facilities plan prioritized across disciplines ever issued by a government science-funding agency anywhere in the world.
The construction approval received today, known as Critical Decision 3 or CD-3, concludes an exhaustive, multi-year review process that clearly established the scientific need, merit and quality of the 12 GeV CEBAF upgrade project. The project will see DOE's Jefferson Lab double the energy of its accelerated electron beam from 6 billion electron volts (GeV) to 12 GeV; construct a new experimental hall; and upgrade the equipment in its three existing experimental halls. Construction funds are requested in the President's Fiscal Year 2009 Budget Request, and project completion is planned for 2015.
"Today's approval is truly historic," said Dr. Jehanne Simon-Gillo, Acting Associate Director of DOE's Office of Science for Nuclear Physics. "The 12 GeV CEBAF upgrade will enable scientists to seek answers to some of Nature's most perplexing questions, expand our knowledge of the universe and benefit people around the world. The project also clearly demonstrates our Nation's commitment to remaining in the forefront of scientific exploration and discovery."
Jefferson Lab is a world-leading nuclear physics research laboratory devoted to the study of the building blocks of matter – quarks and gluons - that make up 99 percent of the mass of our everyday world. Scientists from across the Nation and around the world use the lab's facilities to probe the nucleus of the atom. The upgrade will employ new methods for studying the basic properties of the building blocks of the universe, how they are formed, how they interact and the forces that regulate these interactions.
"This is a very exciting day for all of us at Jefferson Lab; the upgrade will provide a qualitative change with an enormous enhancement to our experimental program enabling higher precision and better resolution," said Jefferson Lab Director Hugh Montgomery. "Many people have worked very hard to get us to this point, the veritable springboard. We look forward to building this wonderful machine and using its world-leading capabilities to learn more about our world."
Through experiments, physicists will use the upgraded accelerator to expand the knowledge of nuclear and particle physics. The upgrade will affect four main areas of study:
- Quark Confinement - With the upgrade, physicists plan to address one of the great mysteries of modern physics - why quarks only exist together, and never alone.
- The Fundamental Structure of Protons and Neutrons - The upgrade will enable scientists to map in detail the distributions of quarks in space and momentum, culminating in tomography measurements that will constitute a three-dimensional picture of the internal structures of protons and neutrons.
- The Physics of Nuclei – The upgrade will allow researchers to illuminate the role of quarks in the structure and properties of atomic nuclei, and how these quarks interact with a dense nuclear medium.
- Tests of the Standard Model - An upgraded facility will allow physicists to study the limits of the "Standard Model," a theory that describes the fundamental particles and their interactions.
To explore protons and neutrons, the CEBAF accelerator propels a beam of electrons at nearly the speed of light around an oval-shaped "racetrack" that is 7/8 mile long and buried 25 feet underground. When the beam smashes into the experimental targets, huge detectors collect the fragments. By studying the speed, direction and energy of the scattered fragments, scientists can unveil the inner secrets of protons and neutrons.
The laboratory, which operates on a 206-acre campus, employs more than 650 people and is a center for nuclear physics research, superconducting accelerator technology, and education. It is one of 17 National Laboratories funded and overseen by DOE. Jefferson Lab is managed and operated by Jefferson Science Associates, LLC, a company formed by the Southeastern Universities Research Association and Computer Sciences Corp.