Two protons and a neutron A discrepancy between two different measurements of the charge radius of the helium-3 nucleus may have been reconciled. (Courtesy: Shutterstock) Independent measurements of ...

New measurements have resolved the proton radius puzzle, confirming a smaller subatomic value of 0.8406 femtometers.

Mystery no more Artist’s conception of the magnetic moment of the muon – a sub-atomic particle similar to, but heavier than, ...

Theoretical calculations predict a complex excited state (0+) for helium-4 (4He) at the 20.21 MeV energy level. This state involves a coupling of three cluster configurations: hydrogen-3 and a proton, ...

For years, one tiny mismatch in particle physics carried outsized hopes. The muon, a heavier and short-lived cousin of the electron, seemed to wobble in a magnetic field just a little differently than ...

The 50-foot-wide racetrack used to study muons traveled by barge around Florida and up the Mississippi, and then by truck across Illinois. Reidar Hahn, Fermilab About 50 years ago, physicists came up ...

Physicists have spent the last 20 years pondering an apparent discrepancy between experimental results and theoretical predictions for the magnetic properties of the muon, the electron’s heavier ...

When the results of an experiment don’t match predictions made by the best theory of the day, something is off. Fifteen years ago, physicists at Brookhaven National Laboratory discovered something ...