Radioactivity
Natural strontium is nonradioactive and nontoxic, but 90Sr is a radioactivity hazard. 90Sr undergoes β− decay with a half-life of 28.79 years and a decay energy of 0.546 MeV distributed to an electron, an anti-neutrino, and the yttrium isotope 90Y, which in turn undergoes β− decay with half-life of 64 hours and decay energy 2.28 MeV distributed to an electron, an anti-neutrino, and 90Zr (zirconium), which is stable. Note that 90Sr/Y is almost a perfectly pure beta source; the gamma photon emission from the decay of 90Y is so infrequent that it can normally be ignored.
Prop: Unit: |
t½ a |
Yield % |
Q * keV |
βγ * |
---|---|---|---|---|
155Eu | 4.76 | .0803 | 252 | βγ |
85Kr | 10.76 | .2180 | 687 | βγ |
113mCd | 14.1 | .0008 | 316 | β |
90Sr | 28.9 | 4.505 | 2826 | β |
137Cs | 30.23 | 6.337 | 1176 | βγ |
121mSn | 43.9 | .00005 | 390 | βγ |
151Sm | 90 | .5314 | 77 | β |
Read more about this topic: Strontium-90