Gamma-ray spectra of a 20-h Fm-255 source containing similar to1 mCi activi
ty were measured with a 25% Ge detector and a low-energy photon spectromete
r (LEPS). Gamma lines with intensities as low as 1.0 x 10(-6)% per 255Fm, d
ecay were observed. Gamma-gamma coincidence spectra of a Fm-255 Sample were
measured with the GAMMASPHERE array. A comparison of the gamma -ray spectr
um gated by the Cf K alpha x-ray peak with the gamma -singles spectrum prov
ided spins of the excited states in Cf-251. The gamma -ray data, in conjunc
tion with previously measured Cf-250(d,p) reaction data, allowed us to char
acterize several single-particle and vibrational states above the N = 152 s
ubshell gap.