Conversion Coefficient Measurements in Sm152, Gd154, and Dy160 by the IEC Method

Abstract

This chapter describes the conversion coefficient measurements in Sm 152 , Gd 154 , and Dy 160 by the internal-external conversion (IEC) method. The κ and L internal conversion coefficients of the pure E2 transitions from the first excited states in Sm 152 , Gd 154 , and Dy 160 and of two E2 and one E1 higher energy transitions in Dy 160 have been measured by the IEC method. The Tb 160 , Eu 152 , and Eu 154 sources are prepared by neturon irradiation of separated Tb 159 , Eu 151 , and Eu 153 . The contamination of Eu 152 in the Eu 154 sample and Eu 154 in the Eu 152 sample was determined to be less than 1% in each case. Three sources of Tb 160 were prepared, two for the internal measurements and one for the external. Two sources—one for internal and one for external studies—were made for each isotope. Six silver converters of different size and thickness were prepared for the external conversion measurements of the 87-, 122-, and 123-keV transitions in Dy 160 , Sm 152 , and Gd 154 respectively. A uranium converter was used for the external measurements of the 879-keV transition.