Measurement of the absolute activity of 235U by the generalized coincidence method

✍ Scribed by Carmen C. Bueno; M.Damy S. Santos

• Publisher: Elsevier Science
• Year: 1993
• Tongue: English
• Weight: 654 KB
• Volume: 44
• Category: Article
• ISSN: 0969-8043
• DOI: 10.1016/0969-8043(93)90171-6

✦ Synopsis

The absolute activity of z'5U contained in a sample was measured utilizing a sum-coincidence circuit which selects only the a-particles emitted simultaneously with the 143 and 186 keV gamma radiations from the 23'Th (product nucleus). The a-particles were detected by means of a new type of a gas scintillating chamber, in which the light emitted by excitation of the gas atoms, due to the passage of a charged incoming particle, has its intensity increased by the action of an applied electric field. The y-radiations were detected by means of a 1" x I 'W NaI(T1) scintillation detector. The value obtained for the half-life of 235U, (7.04 k 0.01) x IO8 y, was compared with the data available from various observers which used different experimental techniques. It is shown that our results are in excellent agreement with the best data available on this subject.