The low-energy capture gamma-ray spectra of ${\mathrm{Eu}}^{152}$ and ${\mathrm{Eu}}^{154}$ have been examined up to an energy of 300 kev by the use of a scintillation spectrometer. ${\mathrm{Eu}}^{152}$ was found to exhibit gamma lines at 81±4 kev and 92±3 kev while ${\mathrm{Eu}}^{154}$ exhibited gamma lines at 75±3 kev and 91±3 kev. Coincidence measurements were made on a composite spectrum produced by thermal neutron capture in natural Eu. The data are consistent with the interpretation that the ${\mathrm{Eu}}^{154}$ lines are members of a rotational band while the ${\mathrm{Eu}}^{152}$ lines are not.

• Received 14 April 1959

DOI:https://doi.org/10.1103/PhysRev.115.1287