Scientists in Japan and South Korea have discovered a previously unknown uranium isotope, uranium-241, with an atomic number of 92, a mass of 241 and a possible half-life of just 40 minutes. It is the first neutron-rich uranium isotope found by scientists since 1979. The research team notes that its method can be used to further understand the isotopes of other heavy elements, and is also expected to find new isotopes. The research appears in the latest issue of the journal Physical Review Letters.

Over the past few decades, physicists have discovered that because it is difficult to synthesize some neutron-rich isotopes of heavy elements, it is also difficult to determine the properties of these isotopes. In light of this, they have been exploring new ways to synthesize neutron-rich isotopes under laboratory conditions.

In the latest study, scientists at the Japan High Energy Accelerator Research Institute (KEK) filled this knowledge gap by determining the masses of 19 such isotopes, including the brand new uranium-241.

The team carried out the latest experiments at the KEK isotope separation System facility. They accelerated a beam of uranium-238 nuclei into a rotating target of a platinum-198 nucleus. This process transferred multiple protons and neutrons between the uranium beam and the platinum target, forming multiple isotopes. They then used a time-of-flight mass spectrometer to determine the masses of these isotopes.

The researchers pinpointed the masses of 19 neutron-rich isotopes of heavy elements that contain anywhere from 143 to 150 neutrons, of which uranium-241 had never been observed before.

The researchers say the techniques used in the latest study could help them better understand the shape of atomic nuclei associated with heavy elements, potentially modify existing models for building nuclear and nuclear power plants, and theories for describing the behavior of exploding stars, as well as the discovery of more new isotopes.