Clues to exotic particles found again

An experiment that found hints of what could be new subatomic particles last year has done it again.

A new analysis of data taken at Brookhaven National Laboratory in Upton, N.Y., shows that particles called muons wobble in a magnetic field faster than predicted by the prevailing theory of particle physics. Because the speed-up can’t be the handiwork of known particles, unknown ones may be responsible, says B.