Jefferson Lab has three experimental halls. Hall A is the largest of these three experimental staging areas. It is 174 feet across and 80 feet tall from the floor to the highest spot on its domed ceiling. The foundation for the hall is 35 feet below ground.
Hall A is outfitted with two primary detector systems – both high-resolution spectrometers, each weighing about 3 million pounds or 1,500 short tons. The hall is used primarily for experiments that study the structure of the nucleus and the protons and neutrons it contains.
Hall A experiments focus on nucleon form factors to high Q2, the strange-quark structure of the proton, nucleon spin structure, few-body form factors to high Q2 and nuclear structure at small inter-nucleon separations.
An international collaboration of scientists participate in experiments carried out in Hall A. Hall collaborators represent more than 70 institutions and 18 countries.
For more information about Hall A experiments, publications and results, technical information and plans for the 12 GeV Upgrade, click here.