Weak Gamma Rays in the Decay of La140

Weak gamma rays of energy 0.63 MeV was found in the decay of La 140 by means of a scintillation summing Compton spectrometer. This gamma rays are ascribed to the transition between the 2.53-MeV and 1.90.MeV states of Ce 140 . The transition between this 1.90-MeV state and the 1.60-MeV state was not detected. The results of the present investigations on the conversion electrons and Gamma rays support the suggestion of Dželepow et al that the 1.90-MeV state is a O + one.