JLab Aerial

In this aerial view of Jefferson Lab and some of the surrounding area, the accelerator site is visible in the foreground. Experimental Halls A, B and C are visible as the three round mounds on the left, and Hall D and its counting house are on the far right. The long, one-story white buildings sit, respectively, over the North and South Linear Accelerator sections of CEBAF.



All visible matter in the universe is built of subatomic particles called quarks and gluons. These particles combine to form the protons and neutrons found in the nucleus of the atom.

Scientists at Jefferson Lab study these particles and the strong force that binds them together. They do this using the Continuous Electron Beam Accelerator Facility (CEBAF) and the lab’s four experimental halls – Halls A, B, C and D.

CEBAF acts like a giant microscope, making it possible for physicists to probe the atom’s nucleus. Big microscopes allow for finer resolution, and that is the case with CEBAF. CEBAF provides an unprecedented view of the basic building blocks of ordinary matter and their interactions, allowing scientists to gain deeper insight into the particles and forces that build our universe.

Quarks come in six flavors: up, down, strange, charm, top and bottom. The strong force binds quarks together so tightly that we never find one alone. The proton, as an example, is built of three quarks (one down and two up quarks) that constantly swap particles called gluons. These gluons carry the strong force, so this swapping of gluons is what "glues" quarks together into protons, neutrons (one up and two down quarks), and other particles.