Kyodo News wrote:Tokyo Electric Power Co. said Wednesday it has observed a neutron beam, a kind of radioactive ray, 13 times on the premises of the Fukushima Daiichi nuclear plant after it was crippled by the massive March 11 quake-tsunami disaster.
TEPCO, the operator of the nuclear plant, said the neutron beam measured about 1.5 kilometers southwest of the plant's No. 1 and 2 reactors over three days from March 13 and is equivalent to 0.01 to 0.02 microsieverts per hour and that this is not a dangerous level.
http://english.kyodonews.jp/news/2011/03/80539.html
Wikipedia wrote:Neutron radiation is a kind of ionizing radiation which consists of free neutrons. A result of nuclear fission or nuclear fusion, it consists of the release of free neutrons from both stable molecules and isotopes, and these free neutrons react with nuclei of other stable molecules to form new isotopes of previously non-isotopic molecules, which in turn produce radiation. This will result in a chain reaction of nuclear radiation, which makes radiation dangerous and harmful over great areas of space.
http://en.wikipedia.org/wiki/Neutron_radiation#Neutron_radiation_and_nuclear_fission
