The Brief Lives of Neutrons

A unique experiment to pin down the neutron’s surprisingly elusive half-life

July 21, 2016

Most neutrons inside atoms are stable. But get one on its own, and it will disintegrate in about ten minutes.
Beam and bottle experiments are strikingly incompatible with one another, differing by nearly six seconds.

Free neutrons are unstable, but it is surprisingly difficult to accurately determine how long neutrons live before decaying. Increasingly high-tech measurements, with ever-smaller uncertainties, are converging to not one but two different answers. Some experiments gather neutrons and count how many remain after an elapsed time. Other experiments count the particles left behind when neutrons decay. Both are expertly done, but their results do not jibe with one another. At Los Alamos National Laboratory, a bold new variation on the neutron-counting experiment aims to resolve this enduring dilemma.

To read the full magazine article, click here.

Originally published at

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