Scientists make the most precise measurement yet of the particle’s weak charge
Protons are no one-trick ponies. Although famous for their positive electric charge, the particles also carry an analogous, lesser-known charge, called the weak charge. Now, physicists have made the most precise measurement of the proton’s underdog attribute, members of the Q-weak experiment report in the May 10 Nature.
The weak charge dictates how the proton responds to the weak nuclear force. Best known for its role in certain types of radioactive decay, the weak force is named for its feebleness compared with other forces such as electromagnetism (SN: 3/3/18, p. 11).
In the experiment, located at the Thomas Jefferson National Accelerator Facility in Newport News, Va., scientists scattered beams of electrons off of protons in liquid hydrogen. The beams came in two different