Alpha Spectrum of 212-Bi Source Prepared using Electrolysis of Non-Enriched ThNO3 Salt

Swapna Gora, B.P. Jithin, V.V.V. Satyanarayana, O.S.K.S Sastri and B.P Ajith

Central University of Himachal Pradesh

We present various aspects involved in performing alpha spectroscopy experiments using non-enriched Th(NO)3 salt. The experimental design is improved in a cyclic fashion to bring forth the importance of thin film preparation of the radioactive source, and creating vacuum in reducing the energy losses due to self-absorption and air scattering respectively. Thin film preparation using electrolysis of ThNO 3 aqueous solution has been optimized for current and time to selectively deposit 212-Bi. The obtained spectrum had large peaks at 6093keV and 8753 keV with resolutions of 2.10% and 2.90% and relative percentage errors of 0.59% and 0.35% respectively. These peaks had intensity ratios of 33.2% : 66.8% matching with existing values in Nuclear Data Tables. Then the concentration (ratio of ThNO 3 :water) has been increased to obtain reasonably large counts within 4 hours so that data can be utilised to obtain half life of 212-Bi. The best obtained half life of Bismuth from the counts saved after every 20 minutes has been determined to be 62.77 ± 0.79 minutes which is close to the expected value of 60.55 ± 0.30 minutes.