کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
1879163 | 1042545 | 2012 | 8 صفحه PDF | دانلود رایگان |
The radioactive concentrations of 166mHo, 134Cs and 133Ba solutions have been standardised using a 4πβ–4πγ coincidence counting system we have recently set up. The detection in the beta channel is performed using various geometries of a UPS-89 plastic scintillator optically coupled to a selected low-noise 1 in. diameter photomultiplier tube. The light-tight thin capsule that encloses this beta detector is housed within the well of a 5 in.×5 in. NaI(Tl) monocrystal detector. The beta detection efficiency can be varied either by optical filtering or electronic discrimination when the electrons loose all their energy in the plastic scintillator. This 4πβ−4πγ coincidence system improves on our 4πβ(PC)–γ system in that its sample preparation is less labour intensive, it yields larger beta- and gamma-counting efficiencies thus enabling the standardisation of low activity sources with good statistics in reasonable time, and it makes standardising short-lived radionuclides easier. The resulting radioactive concentrations of 166mHo, 134Cs and 133Ba are found to agree with those measured with other primary measurement methods thus validating our 4πβ−4πγ coincidence counting system.
► A 4πβ(PS)–4πγ coincidence system was developed.
► This system was successfully used to standardise 166mHo, 134Cs and 133Ba solutions.
► Unlike 4πβ(PC)–γ set-ups, its source preparation is cheap and it yields larger efficiencies.
► It also makes standardising short-lived radionuclides easier.
Journal: Applied Radiation and Isotopes - Volume 70, Issue 1, January 2012, Pages 249–256