E2 properties of the ground state band in $^{248}$Cm

The transuranium nucleus 248 Cm has been Coulomb excited using 641 MeV 136 Xe and 260 MeV 58 Ni projectiles. Only the ground band was excited with measurable cross sections. The E2 transition matrix elements involving the ground-band states up to spin 24 + have been extracted from these Coulomb excitation data using a new semiclassical Coulomb-excitation least-squares search code. The extracted E2 transition matrix elements agree with the spheroidal rigid rotor relation to within the experimental errors. In addition static electric quadrupole moments have been measured up to spin 20 + for the first time for a strongly deformed nucleus, uniquely determining the prolate shape of the ground band of 248 Cm.