The Electron-Ion Collider at Brookhaven National Laboratory

The Electron-Ion Collider (EIC), designed by a partnership between Brookhaven National Laboratory (BNL) and Thomas Jefferson National Accelerator Facility (TJNAF), will seek to answer how nucleons — neutrons and protons — are assembled to form the nuclei of atoms, and uniquely address three profound questions about them:

• How does the mass of the nucleon arise?
• How does the spin of the nucleon arise?
• What are the emergent properties of dense systems of gluons?

The mission need for the new collider was acknowledged by the U.S. Department of Energy, and CD-0 was granted on December 19, 2019.