Physicist Find Precious Measurement of Neutrons Lifespan

The world’s most exact measurement of the Neutrons lifespan has been announced by an international team of physicists led by Indiana University Bloomington academics. The findings were published in the journal Physical Review Letters on October 13th

The team’s findings, including experts from over ten national labs and institutions in the United States and internationally, are more than two-fold better than earlier measures, with an uncertainty of less than one-tenth of a percent.”This work establishes a new gold standard for a measurement that is crucial to such problems as the relative abundances of the elements generated in the early cosmos,” said David Baxter, chair of the Department of Physics at Indiana University Bloomington. “We’re proud of Indiana’s long history as a pioneer in this field.”

Graduate students Nathan Callahan, Maria Dawid, and Francisco Gonzalez; engineer Walt Fox; Rudy Professor of Physics Chen-Yu Liu; research scientist Daniel Salvat; and mechanical technician John Vanderwerp were among the authors at the time of the study.

The scientific purpose of the experiment is to measure how long, on average, a free neutron lives outside the confines of atomic nuclei.The Neutrons used in the study are produced by the Los Alamos Science Center Ultracold source at Los Alamos National Lab.The UCNtau experiment captures these Neutrons, whose temperatures are lowered to nearly absolute zero, inside a bathtub lined with about 4,000 magnets. After waiting 30 to 90 minutes, researchers count the surviving Neutrons in the tub as they’re levitated against gravity by the force of the magnets.