Xenon-133 and -135 are measured at reactor 2. Xenon is daughter of Uranium 235, half life time is 5.2 days (Xenon-133), and 9 hours (Xenon-135).
It proves the nuclear fuel is fissioning at reactor 2 still.
Tepco has starting injecting boric-acid solution into the (broken) reactor.
At reactor 2, Tepco finally started analyzing air filter of the container vessel on 10/28/2011. As the result, they detected xenon-133 and -135. It may have been fissioning since months ago.
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