UBC Theses and Dissertations
A low energy beta-ray spectrometer and the beta-ray spectrum of Eul52-154 Ayers, Walter Revis
Modifications have been made to a semi-circular focussing spectrometer to facilitate its operation and to improve its performance. Geiger counters filled with the saturated vapour of heptane kept in an ice bath are used to detect the beta-particles. The windows of the counters are made of zapon films about 10 micrograms/cm² in thickness. The sources are mounted on similar films and have a total thickness less than 100 micrograms/cm². The combination of thin source and thin windows permits the measurement of beta-particle energies down to 2 Kev. An examination of the beta-spectrum of Eu¹⁵²⁻⁴ has been carried out. It consists of 7 peaks corresponding to the energies 8.0, 15.0, 26.4, 33.2, 38.3, 73.1 and 74.8 Kev. The two upper peaks are assigned as K conversion lines for gamma-rays of 121.5 and 123.2 Kev. The 33.2 and 38.3 Kev lines are assigned as L and M Auger electrons in Sm. The 8.0 Kev line is assigned as an M Auger electron in Sm. The 15.0 Kev peak is assigned tentatively as an M conversion line corresponding to a gamma-ray of 16 Kev. The 26.4 Kev line is tentatively assigned as either a K conversion line corresponding to a gamma-ray of 73 Kev or an L conversion line corresponding to a gamma-ray of 34 Kev.