Violations of K‐Conservation in 178Hf

Coulomb excitation of Kπ=6+(t1/2=77 ns), 8−(t1/2=4.0 s) and 16+(t1/2=31 y) 178Hf isomers has led to the measurement of a set of Eλ matrix elements, coupling the isomer bands to the γ‐ and ground state bands. The resulting matrix elements, derived using a coupled‐channel semiclassical Coulomb excitation search code, have been used to probe the K‐components in the wave functions and revealed the onset and saturation of K‐mixing in low‐K bands, whereas K‐mixing is negligible in the high‐K bands. The implications can be applied to other quadrupole‐deformed nuclei. An upper limit on the Coulomb depopulation yield of the 16+ isomer was calculated based on the present set of matrix elements.