Neutron-rich nucleus shapeshifts between a rugby ball and a discus

An international team led by scientists from IPN Orsay (CNRS/Université Paris-Sud), CEA, and RIKEN (Japan) has performed the first spectroscopy of the extremely neutron-rich isotopes krypton 98 and 100. This experiment showed that there are two coexisting, competing quantum shapes at low energy in 98Kr, never before seen for neutron-rich Kr isotopes. The team also showed that these isotopes experience a gentle onset of deformation with added neutrons, in sharp contrast with neighboring isotopes of rubidium, strontium, and zirconium, which change shapes suddenly at neutron number 60. Read more.