Angular correlations of gamma rays from excited states of ¹⁶⁶Er have been
measured following the β decays of ¹⁶⁶ Ho (Jπ =7-, t 1/2 =1200y, Q= 1854 ke V) and ¹⁶⁶Tm (Jπ = 2+, t 1/2, = 7.7h, Q=3040 keV).
Data was collected using the 8π
spectrometer, an array of...