Mössbauer Effect Studies of the 103-keV Level onEu153

Abstract
The recoilless absorption spectra of the 103-keV γ rays from Eu153m in Eu153 situated in europium oxide and in europium iron garnet were measured at 20°K. The source used was Sm153 in the form of an oxide at 20°K. With the Eu2 O3 absorber an unsplit absorption line with (2.1±0.4) mm/sec width at half-maximum was obtained. From the hyperfine Zeeman splittings obtained with the europium iron garnet absorber, a value of (+2.01±0.09) nm. was found for the magnetic moment of the 103-keV level of the Eu153. This value is in very good agreement with the predictions of the unified model.