Internal and External Conversion Studies on the Decay of ¹⁴³Ce

Abstract

The internal conversion and photoelectron spectra associated with the decay of ¹⁴³Ce to ¹⁴³Pr have been studied using high resolution double focussing beta-ray spectrometers. In addition to gamma rays previously reported five new gamma-rays have been observed. A decay scheme involving q excited levels is suggested for ¹⁴³Pr. The gamma-ray intensities were determined by photoelectron experiments. The internal K-conversion coefficients of all the transitions above 200 keV following the decay of ¹⁴³Ce have been determined absolutely by the method of comparing internal and external conversion lines. Multipolarity data, obtained from the absolute or ratio measurements of conversion coefficients, were utilized for assigning possible spins and parities to the levels of ¹⁴³Pr. The experimental level structure of ¹⁴³Pr is compared with the theoretical predictions.