Exploring the stability of super heavy elements: First Measurement of the Fission Barrier of 254No

The gamma-ray multiplicity and total energy emitted by the heavy nucleus No-254 have been measured at 2 different beam energies. From these measurements, the initial distributions of spin I and excitation energy E* of No-254 were constructed. The distributions display a saturation in excitation energy, which allows a direct determination of the fission barrier. No-254 is the heaviest shell-stabilized nucleus with a measured fission barrier.