cesium-137: half-life 30.2 years, 0.3 MeV beta and 0.66 MeV gamma-ray emitter
1 Gray (Gy) = 1 joule of ionizing energy per kilogram
Energy = 400 Gy•0.25 kg= 100 J
100J/0.3•10⁶•10⁻¹⁹=3.33•10¹⁵ disintegrations
A typical tumor treated with radiotherapy may receive 400 Gy per 250g.
How many disintegrations of caesium-137 atoms are required to provide that absorbed dose?
Help would be appreciated!
1 answer
1 answer