Uncovering the Decay of Tantalum-180m: Nature's Rarest Isotope

Physicists are conducting experiments to measure the radioactive decay of the excited state in Tantalum-180m, an isotope with an expected lifetime approximately 1 million times longer than the age of the universe. This unprecedented opportunity challenges existing theories and models of nuclear structure and decay, with initial data establishing the longest limits ever achieved in nuclear isomer studies. The experiment, conducted at the MAJORANA ultra-low background facility, has significantly enhanced existing limits by one to two orders of magnitude, allowing researchers to dismiss certain parameter ranges associated with potential dark matter particles.