A CIGAR-SHAPED atom has demonstrated a novel kind of radioactive decay by spitting out two free protons at the same time.
Radioactive decay normally involves the emission of one of three types of particle: a helium nucleus consisting of two protons and two neutrons, an electron or a photon. Exotic atoms engineered to contain fewer neutrons than in the atom’s natural state were expected to break down by emitting protons, either one at a time or in pairs. But the two-proton decay had never been seen.
Sam Tabor, a nuclear physicist at Florida State University in Tallahassee, and his colleagues…
