News Physics

Physicists may have finally spotted elusive clusters of four neutrons

If confirmed, ‘tetraneutrons’ could help scientists better understand nuclear forces

illustration of a tetraneutron

Four neutrons may form a short-lived agglomeration called a tetraneutron (illustrated).

Sonja Battenberg/TUM

By Emily Conover

Physicists have found the strongest sign yet of a fabled four of a kind.

For six decades, researchers have hunted for clusters of four neutrons called tetraneutrons. But evidence for their existence has been shaky. Now, scientists say they have observed neutron clusters that appear to be tetraneutrons. The result strengthens the case that the fab four is more than a figment of physicists’ imaginations.