Publication Date:
2014-12-18
Description:
The nuclear isomer \(^{121m_2 } Te\) was synthesized at a cyclotron by the ( d ,2 n ) reaction and then incorporated into the MgO ceramic. This γ-ray source was stored either at 78 or at 298 K. The measured γ-radiation intensity ratio, R = (Φ 573 keV /Φ 212 keV ), at 78 K appeared to be higher by a factor of 1.0012 ± 0.0002 than at 298 K. The temperature dependence of R is caused by the low-temperature increase in the “constant” λ 2 of the \(^{121m_2 } Te \to ^{121m_1 } Te\) decay by the internal conversion mechanism, equal to Δλ 2 /λ 2 = (0.07 ± 0.02)%. The same increase in the decay constant due to induced γ-ray emission, \(^{121m_2 } Te + hv (81.79 keV) \to ^{121m_1 } Te + 2hv (81.79 keV)\) , will be reached if both the size of the \(^{121m_2 } Te\) source and the \(^{121m_2 } Te\) concentration in it will be increased by 3 orders of magnitude, i.e., the total \(^{121m_2 } Te\) activity should be increased by 6 orders of magnitude.
Print ISSN:
1066-3622
Electronic ISSN:
1608-3288
Topics:
Chemistry and Pharmacology
