They have reported that two Xenons, both of which have short half life spans, were possibly found in the 2nd nuclear reactor in the crippled nuclear power plant in Fukushima. This means that it could goes critical recently.
As told in the previous post, the 3 reactors underwent the melt-through down to the secondary containment. The authority had triumphantly insisted, with "the evidence of measurement of lowered temp at the reactor", they had achieved the cooling arrest of the nuclear reactors some time ago. If there was really Xenons detected there, this statement turns out to be false. On the whole, we don't know what has been going on with these reactors in the melt through.
They announce that there is no substantial change of the radiation around the reactor. No date as for the neutron emission from the reactor area, though. The raw data of the measurement of the neutron in elapse is mandatory. We should claim them to show all the data available.
They have already poured Boron to stop the possible criticality into the nuclear reactor. So far, it is not likely that the reactor has gone critical yet. But this event has taught us the nuclear power plant accident has never been out of danger yet. The technology of nuclear reaction is not controllable yet.