How to measure half life of long lived radioactive isotopes such as 10^22 years?
Half life determination: Part 6 Determination of t 1/2 ~ 10 ^22 years or more Longest half life measured till date There are several radioisotopes which decays very very slowly with half life of i.e. quintillion to septillion ( 10^18 - 10^24 ) years. It is very difficult to detect the rare decay events and generated signals out of their decay. One of such radioisotope is alpha emitter 209Bi. The decay heat and light was trapped by using high sensitivity BGO (Bi4Ge3O12) scintillating and optical bolometer. The obtained t 1/2 was 1.9 (± 0.2) × 10^19 years [ De Marcillac, P. et al (2003) ]. Half life of two-neutrino double beta decay (2β2 ν ) decay emitter 150Nd was estimated using Time Projection Chamber [ Artemiev, V. et al (1991) ]. The estimated half life was 1.88(±0.19)× 10^19 years [ Artemiev, V. et al (1995) ]. So far longest half life measured till today directly was of ...
