By Peter Weiss
Deep underground, in a cavern beside the Gran Sasso Tunnel in the Apennines Mountains near Rome, physicists are stacking blocks made of small, transparent crystals containing the isotope tellurium-130. It’s one of only a handful of isotopes expected to undergo a proposed sort of nuclear disintegration. Within months, Ettore Fiorini of the University of Milan-Bicocca in Milan, Italy, and
his colleagues expect their stack of crystals to begin serving as a detector of the long-sought disintegration, known as neutrinoless double-beta decay. Other researchers, conducting different types of experiments using other isotopes, are hunting for the same trophy. One group claims to already have it, but other scientists are skeptical of the finding.